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Benchetrit S, Badariotti JI, Corbett J, Costello JT. The effects of sleep deprivation and extreme exertion on cognitive performance at the world-record breaking Suffolk Back Yard Ultra-marathon. PLoS One 2024; 19:e0299475. [PMID: 38483945 PMCID: PMC10939274 DOI: 10.1371/journal.pone.0299475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 02/09/2024] [Indexed: 03/17/2024] Open
Abstract
Using a prospective observational design, this study investigated the hypothesis that competing in the Suffolk Back Yard Ultra-marathon, would result in impaired cognitive performance and examined whether pre-race sleep patterns could mitigate this. Fifteen runners (1 female) volunteered to undertake this study and eleven males were included in the final analysis. Before the race and after withdrawal participants completed the following cognitive performance tasks: 2 Choice Reaction Time (2CRT), Stroop, and the Tower Puzzle. Pre-race sleep strategies were subjectively recorded with a 7-day sleep diary. Following race withdrawal, reaction time increased (Δ 77±68 ms; p = 0.004) in the 2CRT and executive function was impaired in the Stroop task (Interference score Δ -4.3±5.6 a.u.; p = 0.028). Decision making was not affected in the Tower Puzzle task. There was a significant correlation between the pre-race 7-day average sleep scores and both 2CRT Δ throughput (r = 0.61; p = 0.045) and 2CRT Δ RT (r = -0.64; p = 0.034). This study supports the hypothesis that running an ultra-marathon, which includes at least one night of sleep deprivation, impairs cognitive performance and provides novel evidence suggesting good sleep quality, in the week prior to an ultra-marathon, could minimise these effects.
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Affiliation(s)
- Sandy Benchetrit
- Extreme Environments Thematic Research Group, School of Sport, Health & Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
- Gloucestershire Hospitals NHS Foundation Trust, Gloucestershire Royal Hospital, Gloucester, United Kingdom
| | - Juan I. Badariotti
- Extreme Environments Thematic Research Group, School of Sport, Health & Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Jo Corbett
- Extreme Environments Thematic Research Group, School of Sport, Health & Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Joseph T. Costello
- Extreme Environments Thematic Research Group, School of Sport, Health & Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
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Temmar H, Willsey MS, Costello JT, Mender MJ, Cubillos LH, Lam JL, Wallace DM, Kelberman MM, Patil PG, Chestek CA. Artificial neural network for brain-machine interface consistently produces more naturalistic finger movements than linear methods. bioRxiv 2024:2024.03.01.583000. [PMID: 38496403 PMCID: PMC10942378 DOI: 10.1101/2024.03.01.583000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Brain-machine interfaces (BMI) aim to restore function to persons living with spinal cord injuries by 'decoding' neural signals into behavior. Recently, nonlinear BMI decoders have outperformed previous state-of-the-art linear decoders, but few studies have investigated what specific improvements these nonlinear approaches provide. In this study, we compare how temporally convolved feedforward neural networks (tcFNNs) and linear approaches predict individuated finger movements in open and closed-loop settings. We show that nonlinear decoders generate more naturalistic movements, producing distributions of velocities 85.3% closer to true hand control than linear decoders. Addressing concerns that neural networks may come to inconsistent solutions, we find that regularization techniques improve the consistency of tcFNN convergence by 194.6%, along with improving average performance, and training speed. Finally, we show that tcFNN can leverage training data from multiple task variations to improve generalization. The results of this study show that nonlinear methods produce more naturalistic movements and show potential for generalizing over less constrained tasks. Teaser A neural network decoder produces consistent naturalistic movements and shows potential for real-world generalization through task variations.
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Williams TB, Badariotti JI, Corbett J, Miller-Dicks M, Neupert E, McMorris T, Ando S, Parker MO, Thelwell RC, Causer AJ, Young JS, Mayes HS, White DK, de Carvalho FA, Tipton MJ, Costello JT. The effects of sleep deprivation, acute hypoxia, and exercise on cognitive performance: A multi-experiment combined stressors study. Physiol Behav 2024; 274:114409. [PMID: 37977251 DOI: 10.1016/j.physbeh.2023.114409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 11/08/2023] [Accepted: 11/11/2023] [Indexed: 11/19/2023]
Abstract
INTRODUCTION Both sleep deprivation and hypoxia have been shown to impair executive function. Conversely, moderate intensity exercise is known to improve executive function. In a multi-experiment study, we tested the hypotheses that moderate intensity exercise would ameliorate any decline in executive function after i) three consecutive nights of partial sleep deprivation (PSD) (Experiment 1) and ii) the isolated and combined effects of a single night of total sleep deprivation (TSD) and acute hypoxia (Experiment 2). METHODS Using a rigorous randomised controlled crossover design, 12 healthy participants volunteered in each experiment (24 total, 5 females). In both experiments seven executive function tasks (2-choice reaction time, logical relations, manikin, mathematical processing, 1-back, 2-back, 3-back) were completed at rest and during 20 min semi-recumbent, moderate intensity cycling. Tasks were completed in the following conditions: before and after three consecutive nights of PSD and habitual sleep (Experiment 1) and in normoxia and acute hypoxia (FIO2 = 0.12) following one night of habitual sleep and one night of TSD (Experiment 2). RESULTS Although the effects of three nights of PSD on executive functions were inconsistent, one night of TSD (regardless of hypoxic status) reduced executive functions. Significantly, regardless of sleep or hypoxic status, executive functions are improved during an acute bout of moderate intensity exercise. CONCLUSION These novel data indicate that moderate intensity exercise improves executive function performance after both PSD and TSD, regardless of hypoxic status. The key determinants and/or mechanism(s) responsible for this improvement still need to be elucidated. Future work should seek to identify these mechanisms and translate these significant findings into occupational and skilled performance settings.
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Affiliation(s)
- Thomas B Williams
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Juan I Badariotti
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom; Department of Psychology, University of Portsmouth, Portsmouth, United Kingdom
| | - Jo Corbett
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Matt Miller-Dicks
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Emma Neupert
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Terry McMorris
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom; Department of Sport and Exercise Sciences, University of Chichester, Chichester, United Kingdom
| | - Soichi Ando
- Graduate School of Informatics and Engineering, The University of Electro-Communications, Tokyo, Japan
| | - Matthew O Parker
- Surrey Sleep Research Centre, School of Biosciences, University of Surrey, Guildford, United Kingdom
| | - Richard C Thelwell
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Adam J Causer
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - John S Young
- National Horizons Centre, Teesside University, Darlington, United Kingdom; School of Health and Life Sciences, Teesside University, Middlesbrough, United Kingdom
| | - Harry S Mayes
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Danny K White
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | | | - Michael J Tipton
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Joseph T Costello
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom.
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Ando S, Fujimoto T, Sudo M, Watanuki S, Hiraoka K, Takeda K, Takagi Y, Kitajima D, Mochizuki K, Matsuura K, Katagiri Y, Nasir FM, Lin Y, Fujibayashi M, Costello JT, McMorris T, Ishikawa Y, Funaki Y, Furumoto S, Watabe H, Tashiro M. The neuromodulatory role of dopamine in improved reaction time by acute cardiovascular exercise. J Physiol 2024; 602:461-484. [PMID: 38165254 DOI: 10.1113/jp285173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Accepted: 12/06/2023] [Indexed: 01/03/2024] Open
Abstract
Acute cardiovascular physical exercise improves cognitive performance, as evidenced by a reduction in reaction time (RT). However, the mechanistic understanding of how this occurs is elusive and has not been rigorously investigated in humans. Here, using positron emission tomography (PET) with [11 C]raclopride, in a multi-experiment study we investigated whether acute exercise releases endogenous dopamine (DA) in the brain. We hypothesized that acute exercise augments the brain DA system, and that RT improvement is correlated with this endogenous DA release. The PET study (Experiment 1: n = 16) demonstrated that acute physical exercise released endogenous DA, and that endogenous DA release was correlated with improvements in RT of the Go/No-Go task. Thereafter, using two electrical muscle stimulation (EMS) studies (Experiments 2 and 3: n = 18 and 22 respectively), we investigated what triggers RT improvement. The EMS studies indicated that EMS with moderate arm cranking improved RT, but RT was not improved following EMS alone or EMS combined with no load arm cranking. The novel mechanistic findings from these experiments are: (1) endogenous DA appears to be an important neuromodulator for RT improvement and (2) RT is only altered when exercise is associated with central signals from higher brain centres. Our findings explain how humans rapidly alter their behaviour using neuromodulatory systems and have significant implications for promotion of cognitive health. KEY POINTS: Acute cardiovascular exercise improves cognitive performance, as evidenced by a reduction in reaction time (RT). However, the mechanistic understanding of how this occurs is elusive and has not been rigorously investigated in humans. Using the neurochemical specificity of [11 C]raclopride positron emission tomography, we demonstrated that acute supine cycling released endogenous dopamine (DA), and that this release was correlated with improved RT. Additional electrical muscle stimulation studies demonstrated that peripherally driven muscle contractions (i.e. exercise) were insufficient to improve RT. The current study suggests that endogenous DA is an important neuromodulator for RT improvement, and that RT is only altered when exercise is associated with central signals from higher brain centres.
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Affiliation(s)
- Soichi Ando
- Graduate School of Informatics and Engineering, The University of Electro-Communications, Tokyo, Japan
- Cyclotron and Radioisotope Centre, Tohoku University, Miyagi, Japan
| | - Toshihiko Fujimoto
- Institute of Excellence in Higher Education, Tohoku University, Miyagi, Japan
| | - Mizuki Sudo
- Meiji Yasuda Life Foundation of Health and Welfare, Tokyo, Japan
| | - Shoichi Watanuki
- Cyclotron and Radioisotope Centre, Tohoku University, Miyagi, Japan
| | - Kotaro Hiraoka
- Cyclotron and Radioisotope Centre, Tohoku University, Miyagi, Japan
| | - Kazuko Takeda
- Cyclotron and Radioisotope Centre, Tohoku University, Miyagi, Japan
| | - Yoko Takagi
- Graduate School of Informatics and Engineering, The University of Electro-Communications, Tokyo, Japan
| | - Daisuke Kitajima
- Faculty of Informatics and Engineering, The University of Electro-Communications, Tokyo, Japan
| | - Kodai Mochizuki
- Graduate School of Informatics and Engineering, The University of Electro-Communications, Tokyo, Japan
| | - Koki Matsuura
- Graduate School of Informatics and Engineering, The University of Electro-Communications, Tokyo, Japan
| | - Yuki Katagiri
- Graduate School of Informatics and Engineering, The University of Electro-Communications, Tokyo, Japan
| | - Fairuz Mohd Nasir
- Cyclotron and Radioisotope Centre, Tohoku University, Miyagi, Japan
- Faculty of Health Sciences, University Sultan Zainal Abidin, Malaysia
| | - Yuchen Lin
- Cyclotron and Radioisotope Centre, Tohoku University, Miyagi, Japan
- Department of Occupational Therapy, Da-Yeh University, Changhua, Taiwan
| | | | - Joseph T Costello
- Extreme Environments Laboratory, School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, UK
| | - Terry McMorris
- Extreme Environments Laboratory, School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, UK
- Institue of Sport, Nursing and Allied Health, University of Chichester, Chichester, UK
| | - Yoichi Ishikawa
- Cyclotron and Radioisotope Centre, Tohoku University, Miyagi, Japan
| | - Yoshihito Funaki
- Cyclotron and Radioisotope Centre, Tohoku University, Miyagi, Japan
| | - Shozo Furumoto
- Cyclotron and Radioisotope Centre, Tohoku University, Miyagi, Japan
| | - Hiroshi Watabe
- Cyclotron and Radioisotope Centre, Tohoku University, Miyagi, Japan
| | - Manabu Tashiro
- Cyclotron and Radioisotope Centre, Tohoku University, Miyagi, Japan
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Malaga KA, Houshmand L, Costello JT, Chandrasekaran J, Chou KL, Patil PG. Thalamic Segmentation and Neural Activation Modeling Based on Individual Tissue Microstructure in Deep Brain Stimulation for Essential Tremor. Neuromodulation 2023; 26:1689-1698. [PMID: 36470728 DOI: 10.1016/j.neurom.2022.09.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 08/08/2022] [Accepted: 09/13/2022] [Indexed: 12/05/2022]
Abstract
OBJECTIVE Thalamic deep brain stimulation (DBS) is the primary surgical therapy for essential tremor (ET). Thalamic DBS traditionally uses an atlas-based targeting approach, which, although nominally accurate, may obscure individual anatomic differences from population norms. The objective of this study was to compare this traditional atlas-based approach with a novel quantitative modeling methodology grounded in individual tissue microstructure (N-of-1 approach). MATERIALS AND METHODS The N-of-1 approach uses individual patient diffusion tensor imaging (DTI) data to perform thalamic segmentation and volume of tissue activation (VTA) modeling. For each patient, the thalamus was individually segmented into 13 nuclei using DTI-based k-means clustering. DBS-induced VTAs associated with tremor suppression and side effects were then computed for each patient with finite-element electric-field models incorporating DTI microstructural data. Results from N-of-1 and traditional atlas-based modeling were compared for a large cohort of patients with ET treated with thalamic DBS. RESULTS The size and shape of individual N-of-1 thalamic nuclei and VTAs varied considerably across patients (N = 22). For both methods, tremor-improving therapeutic VTAs showed similar overlap with motor thalamic nuclei and greater motor than sensory nucleus overlap. For VTAs producing undesirable sustained paresthesia, 94% of VTAs overlapped with N-of-1 sensory thalamus estimates, whereas 74% of atlas-based segmentations overlapped. For VTAs producing dysarthria/motor contraction, the N-of-1 approach predicted greater spread beyond the thalamus into the internal capsule and adjacent structures than the atlas-based method. CONCLUSIONS Thalamic segmentation and VTA modeling based on individual tissue microstructure explain therapeutic stimulation equally well and side effects better than a traditional atlas-based method in DBS for ET. The N-of-1 approach may be useful in DBS targeting and programming, particularly when patient neuroanatomy deviates from population norms.
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Affiliation(s)
- Karlo A Malaga
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Layla Houshmand
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Joseph T Costello
- Department of Electrical Engineering, University of Michigan, Ann Arbor, MI, USA
| | | | - Kelvin L Chou
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA; Department of Neurosurgery, University of Michigan, Ann Arbor, MI, USA
| | - Parag G Patil
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA; Department of Neurology, University of Michigan, Ann Arbor, MI, USA; Department of Neurosurgery, University of Michigan, Ann Arbor, MI, USA.
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Corbett J, Young JS, Tipton MJ, Costello JT, Williams TB, Walker EF, Lee BJ, Stevens CE. Molecular biomarkers for assessing the heat-adapted phenotype: a narrative scoping review. J Physiol Sci 2023; 73:26. [PMID: 37848829 DOI: 10.1186/s12576-023-00882-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 10/03/2023] [Indexed: 10/19/2023]
Abstract
Heat acclimation/acclimatisation (HA) mitigates heat-related decrements in physical capacity and heat-illness risk and is a widely advocated countermeasure for individuals operating in hot environments. The efficacy of HA is typically quantified by assessing the thermo-physiological responses to a standard heat acclimation state test (i.e. physiological biomarkers), but this can be logistically challenging, time consuming, and expensive. A valid molecular biomarker of HA would enable evaluation of the heat-adapted state through the sampling and assessment of a biological medium. This narrative review examines candidate molecular biomarkers of HA, highlighting the poor sensitivity and specificity of these candidates and identifying the current lack of a single 'standout' biomarker. It concludes by considering the potential of multivariable approaches that provide information about a range of physiological systems, identifying a number of challenges that must be overcome to develop a valid molecular biomarker of the heat-adapted state, and highlighting future research opportunities.
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Affiliation(s)
- J Corbett
- Extreme Environments Laboratory, School of Sport Health and Exercise Sciences, University of Portsmouth, Portsmouth, UK.
| | - J S Young
- National Horizons Centre, Teesside University, Darlington, UK
| | - M J Tipton
- Extreme Environments Laboratory, School of Sport Health and Exercise Sciences, University of Portsmouth, Portsmouth, UK
| | - J T Costello
- Extreme Environments Laboratory, School of Sport Health and Exercise Sciences, University of Portsmouth, Portsmouth, UK
| | - T B Williams
- Extreme Environments Laboratory, School of Sport Health and Exercise Sciences, University of Portsmouth, Portsmouth, UK
| | - E F Walker
- Defence Science and Technology Laboratory, Porton Down, Salisbury, UK
| | - B J Lee
- Occupational and Environmental Physiology Group, Centre for Sport, Exercise and Life Sciences, Faculty of Health and Life Sciences, Coventry University, Coventry, UK
| | - C E Stevens
- Extreme Environments Laboratory, School of Sport Health and Exercise Sciences, University of Portsmouth, Portsmouth, UK
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Wallace DM, Benyamini M, Nason-Tomaszewski SR, Costello JT, Cubillos LH, Mender MJ, Temmar H, Willsey MS, Patil PG, Chestek CA, Zacksenhouse M. Error detection and correction in intracortical brain-machine interfaces controlling two finger groups. J Neural Eng 2023; 20:046037. [PMID: 37567222 PMCID: PMC10594236 DOI: 10.1088/1741-2552/acef95] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 08/01/2023] [Accepted: 08/11/2023] [Indexed: 08/13/2023]
Abstract
Objective.While brain-machine interfaces (BMIs) are promising technologies that could provide direct pathways for controlling the external world and thus regaining motor capabilities, their effectiveness is hampered by decoding errors. Previous research has demonstrated the detection and correction of BMI outcome errors, which occur at the end of trials. Here we focus on continuous detection and correction of BMI execution errors, which occur during real-time movements.Approach.Two adult male rhesus macaques were implanted with Utah arrays in the motor cortex. The monkeys performed single or two-finger group BMI tasks where a Kalman filter decoded binned spiking-band power into intended finger kinematics. Neural activity was analyzed to determine how it depends not only on the kinematics of the fingers, but also on the distance of each finger-group to its target. We developed a method to detect erroneous movements, i.e. consistent movements away from the target, from the same neural activity used by the Kalman filter. Detected errors were corrected by a simple stopping strategy, and the effect on performance was evaluated.Mainresults.First we show that including distance to target explains significantly more variance of the recorded neural activity. Then, for the first time, we demonstrate that neural activity in motor cortex can be used to detect execution errors during BMI controlled movements. Keeping false positive rate below5%, it was possible to achieve mean true positive rate of28.1%online. Despite requiring 200 ms to detect and react to suspected errors, we were able to achieve a significant improvement in task performance via reduced orbiting time of one finger group.Significance.Neural activity recorded in motor cortex for BMI control can be used to detect and correct BMI errors and thus to improve performance. Further improvements may be obtained by enhancing classification and correction strategies.
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Affiliation(s)
- Dylan M Wallace
- Department of Robotics, University of Michigan, Ann Arbor, MI, United States of America
| | - Miri Benyamini
- BCI for Rehabilitation Lab., Faculty of Mechanical Engineering, Technion - Israel Institute of Technology, Haifa, Israel
| | - Samuel R Nason-Tomaszewski
- Cortical Neural Prosthetics Lab., Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States of America
| | - Joseph T Costello
- Department of Electrical and Computer Engineering, University of Michigan, Ann Arbor, MI, United States of America
| | - Luis H Cubillos
- Department of Robotics, University of Michigan, Ann Arbor, MI, United States of America
| | - Matthew J Mender
- Cortical Neural Prosthetics Lab., Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States of America
| | - Hisham Temmar
- Cortical Neural Prosthetics Lab., Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States of America
| | - Matthew S Willsey
- Cortical Neural Prosthetics Lab., Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States of America
- Department of Neurosurgery, University of Michigan, Ann Arbor, MI, United States of America
| | - Parag G Patil
- Cortical Neural Prosthetics Lab., Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States of America
- Department of Neurosurgery, University of Michigan, Ann Arbor, MI, United States of America
| | - Cynthia A Chestek
- Department of Robotics, University of Michigan, Ann Arbor, MI, United States of America
- Cortical Neural Prosthetics Lab., Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States of America
- Department of Electrical and Computer Engineering, University of Michigan, Ann Arbor, MI, United States of America
| | - Miriam Zacksenhouse
- BCI for Rehabilitation Lab., Faculty of Mechanical Engineering, Technion - Israel Institute of Technology, Haifa, Israel
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Mender MJ, Nason-Tomaszewski SR, Temmar H, Costello JT, Wallace DM, Willsey MS, Ganesh Kumar N, Kung TA, Patil P, Chestek CA. The impact of task context on predicting finger movements in a brain-machine interface. eLife 2023; 12:82598. [PMID: 37284744 DOI: 10.7554/elife.82598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 05/22/2023] [Indexed: 06/08/2023] Open
Abstract
A key factor in the clinical translation of brain-machine interfaces (BMIs) for restoring hand motor function will be their robustness to changes in a task. With functional electrical stimulation (FES) for example, the patient's own hand will be used to produce a wide range of forces in otherwise similar movements. To investigate the impact of task changes on BMI performance, we trained two rhesus macaques to control a virtual hand with their physical hand while we added springs to each finger group (index or middle-ring-small) or altered their wrist posture. Using simultaneously recorded intracortical neural activity, finger positions, and electromyography, we found that decoders trained in one context did not generalize well to other contexts, leading to significant increases in prediction error, especially for muscle activations. However, with respect to online BMI control of the virtual hand, changing either the decoder training task context or the hand's physical context during online control had little effect on online performance. We explain this dichotomy by showing that the structure of neural population activity remained similar in new contexts, which could allow for fast adjustment online. Additionally, we found that neural activity shifted trajectories proportional to the required muscle activation in new contexts. This shift in neural activity possibly explains biases to off-context kinematic predictions and suggests a feature that could help predict different magnitude muscle activations while producing similar kinematics.
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Affiliation(s)
- Matthew J Mender
- Department of Biomedical Engineering, University of Michigan-Ann Arbor, Ann Arbor, United States
| | | | - Hisham Temmar
- Department of Biomedical Engineering, University of Michigan-Ann Arbor, Ann Arbor, United States
| | - Joseph T Costello
- Department of Electrical Engineering and Computer Science, University of Michigan-Ann Arbor, Ann Arbor, United States
| | - Dylan M Wallace
- Department of Robotics, University of Michigan-Ann Arbor, Ann Arbor, United States
| | - Matthew S Willsey
- Department of Biomedical Engineering, University of Michigan-Ann Arbor, Ann Arbor, United States
| | - Nishant Ganesh Kumar
- Department of Surgery, University of Michigan-Ann Arbor, Ann Arbor, United States
| | - Theodore A Kung
- Department of Surgery, University of Michigan-Ann Arbor, Ann Arbor, United States
| | - Parag Patil
- Department of Biomedical Engineering, University of Michigan-Ann Arbor, Ann Arbor, United States
| | - Cynthia A Chestek
- Department of Biomedical Engineering, University of Michigan-Ann Arbor, Ann Arbor, United States
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Costello JT, Temmar H, Cubillos LH, Mender MJ, Wallace DM, Willsey MS, Patil PG, Chestek CA. Balancing Memorization and Generalization in RNNs for High Performance Brain-Machine Interfaces. bioRxiv 2023:2023.05.28.542435. [PMID: 37292755 PMCID: PMC10245969 DOI: 10.1101/2023.05.28.542435] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Brain-machine interfaces (BMIs) can restore motor function to people with paralysis but are currently limited by the accuracy of real-time decoding algorithms. Recurrent neural networks (RNNs) using modern training techniques have shown promise in accurately predicting movements from neural signals but have yet to be rigorously evaluated against other decoding algorithms in a closed-loop setting. Here we compared RNNs to other neural network architectures in real-time, continuous decoding of finger movements using intracortical signals from nonhuman primates. Across one and two finger online tasks, LSTMs (a type of RNN) outperformed convolutional and transformer-based neural networks, averaging 18% higher throughput than the convolution network. On simplified tasks with a reduced movement set, RNN decoders were allowed to memorize movement patterns and matched able-bodied control. Performance gradually dropped as the number of distinct movements increased but did not go below fully continuous decoder performance. Finally, in a two-finger task where one degree-of-freedom had poor input signals, we recovered functional control using RNNs trained to act both like a movement classifier and continuous decoder. Our results suggest that RNNs can enable functional real-time BMI control by learning and generating accurate movement patterns.
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10
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Mayes HS, Navarro M, Satchell LP, Tipton MJ, Ando S, Costello JT. The effects of manipulating the visual environment on thermal perception: A structured narrative review. J Therm Biol 2023; 112:103488. [PMID: 36796929 DOI: 10.1016/j.jtherbio.2023.103488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Revised: 01/14/2023] [Accepted: 01/15/2023] [Indexed: 01/26/2023]
Abstract
When exposed to ambient temperatures that cause thermal discomfort, a human's behavioral responses are more effective than autonomic ones at compensating for thermal imbalance. These behavioral thermal responses are typically directed by an individual's perception of the thermal environment. Perception of the environment is a holistic amalgamation of human senses, and in some circumstances, humans prioritize visual information. Existing research has considered this in the specific case of thermal perception, and this review investigates the state of the literature examining this effect. We identify the frameworks, research rationales, and potential mechanisms that underpin the evidence base in this area. Our review identified 31 experiments, comprising 1392 participants that met the inclusion criteria. Methodological heterogeneity was observed in the assessment of thermal perception, and a variety of methods were employed to manipulate the visual environment. However, the majority of the included experiments (80%) reported a difference in thermal perception after the visual environment was manipulated. There was limited research exploring any effects on physiological variables (e.g. skin and core temperature). This review has wide-ranging implications for the broad discipline of (thermo)physiology, psychology, psychophysiology, neuroscience, ergonomics, and behavior.
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Affiliation(s)
- Harry S Mayes
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, England, UK
| | - Martina Navarro
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, England, UK
| | - Liam P Satchell
- Department of Psychology, University of Winchester, Winchester, UK
| | - Michael J Tipton
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, England, UK
| | - Soichi Ando
- Graduate School of Informatics and Engineering, The University of Electro-Communications, Tokyo, Japan
| | - Joseph T Costello
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, England, UK.
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11
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Willsey MS, Nason-Tomaszewski SR, Ensel SR, Temmar H, Mender MJ, Costello JT, Patil PG, Chestek CA. Real-time brain-machine interface in non-human primates achieves high-velocity prosthetic finger movements using a shallow feedforward neural network decoder. Nat Commun 2022; 13:6899. [PMID: 36371498 PMCID: PMC9653378 DOI: 10.1038/s41467-022-34452-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 10/25/2022] [Indexed: 11/13/2022] Open
Abstract
Despite the rapid progress and interest in brain-machine interfaces that restore motor function, the performance of prosthetic fingers and limbs has yet to mimic native function. The algorithm that converts brain signals to a control signal for the prosthetic device is one of the limitations in achieving rapid and realistic finger movements. To achieve more realistic finger movements, we developed a shallow feed-forward neural network to decode real-time two-degree-of-freedom finger movements in two adult male rhesus macaques. Using a two-step training method, a recalibrated feedback intention-trained (ReFIT) neural network is introduced to further improve performance. In 7 days of testing across two animals, neural network decoders, with higher-velocity and more natural appearing finger movements, achieved a 36% increase in throughput over the ReFIT Kalman filter, which represents the current standard. The neural network decoders introduced herein demonstrate real-time decoding of continuous movements at a level superior to the current state-of-the-art and could provide a starting point to using neural networks for the development of more naturalistic brain-controlled prostheses.
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Affiliation(s)
- Matthew S. Willsey
- grid.214458.e0000000086837370Department of Neurosurgery, University of Michigan, Ann Arbor, MI USA ,grid.214458.e0000000086837370Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI USA
| | - Samuel R. Nason-Tomaszewski
- grid.214458.e0000000086837370Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI USA
| | - Scott R. Ensel
- grid.214458.e0000000086837370Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI USA
| | - Hisham Temmar
- grid.214458.e0000000086837370Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI USA
| | - Matthew J. Mender
- grid.214458.e0000000086837370Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI USA
| | - Joseph T. Costello
- grid.214458.e0000000086837370Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI USA
| | - Parag G. Patil
- grid.214458.e0000000086837370Department of Neurosurgery, University of Michigan, Ann Arbor, MI USA ,grid.214458.e0000000086837370Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI USA ,grid.214458.e0000000086837370Neuroscience Graduate Program, University of Michigan Medical School, Ann Arbor, MI USA ,grid.214458.e0000000086837370Department of Anesthesiology, University of Michigan, Ann Arbor, MI USA
| | - Cynthia A. Chestek
- grid.214458.e0000000086837370Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI USA ,grid.214458.e0000000086837370Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI USA ,grid.214458.e0000000086837370Neuroscience Graduate Program, University of Michigan Medical School, Ann Arbor, MI USA ,grid.214458.e0000000086837370Robotics Graduate Program, University of Michigan, Ann Arbor, MI USA ,grid.214458.e0000000086837370Biointerfaces Institute, University of Michigan, Ann Arbor, MI USA
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12
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Sudo M, Costello JT, McMorris T, Ando S. The effects of acute high-intensity aerobic exercise on cognitive performance: A structured narrative review. Front Behav Neurosci 2022; 16:957677. [PMID: 36212191 PMCID: PMC9538359 DOI: 10.3389/fnbeh.2022.957677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 08/29/2022] [Indexed: 11/13/2022] Open
Abstract
It is well established that acute moderate-intensity exercise improves cognitive performance. However, the effects of acute high-intensity aerobic exercise on cognitive performance have not been well characterized. In this review, we summarize the literature investigating the exercise-cognition interaction, especially focusing on high-intensity aerobic exercise. We discuss methodological and physiological factors that potentially mediate cognitive performance in response to high-intensity exercise. We propose that the effects of high-intensity exercise on cognitive performance are primarily affected by the timing of cognitive task (during vs. after exercise, and the time delay after exercise). In particular, cognitive performance is more likely to be impaired during high-intensity exercise when both cognitive and physiological demands are high and completed simultaneously (i.e., the dual-task paradigm). The effects may also be affected by the type of cognitive task, physical fitness, exercise mode/duration, and age. Second, we suggest that interactions between changes in regional cerebral blood flow (CBF), cerebral oxygenation, cerebral metabolism, neuromodulation by neurotransmitters/neurotrophic factors, and a variety of psychological factors are promising candidates that determine cognitive performance in response to acute high-intensity exercise. The present review has implications for recreational, sporting, and occupational activities where high cognitive and physiological demands are required to be completed concurrently.
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Affiliation(s)
- Mizuki Sudo
- Physical Fitness Research Institute, Meiji Yasuda Life Foundation of Health and Welfare, Tokyo, Japan
- *Correspondence: Mizuki Sudo,
| | - Joseph T. Costello
- Extreme Environments Laboratory, School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Terry McMorris
- Extreme Environments Laboratory, School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
- Institute of Sport, University of Chichester, Chichester, United Kingdom
| | - Soichi Ando
- Graduate School of Informatics and Engineering, The University of Electro-Communications, Chofu, Japan
- Soichi Ando,
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13
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Osborne JO, Minett GM, Stewart IB, Trost S, Drovandi C, Costello JT, Pavey TG, Borg DN. Evidence that heat acclimation training may alter sleep and incidental activity. Eur J Sport Sci 2022:1-10. [PMID: 36106465 DOI: 10.1080/17461391.2022.2124386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
This randomized cross-over study tested the hypothesis that heat acclimation training would detrimentally affect sleep variables and alter incidental physical activity compared to a thermoneutral training control condition. Eight recreationally trained males (V̇O2peak 49±4.9 mL.kg-1.min-1) completed two separate interventions separated by at least 31 days: 5 consecutive day training blocks of moderate-intensity cycling (60 min·day-1 at 50% peak power output) in a hot (34.9±0.7 °C and 53±4 % relative humidity) and a temperate (22.2±2.6 °C; 65±8 % relative humidity) environment. Wrist-mounted accelerometers were worn continuously for the length of the training blocks and recorded physical activity, sleep quality and quantity. Data were analysed in a Bayesian framework, with the results presented as the posterior probability that a coefficient was greater or less than zero. Compared to the temperate training environment, heat acclimation impaired sleep efficiency (Pr β<0 = .979) and wake on sleep onset (Pr β>0 = .917). Daily sedentary time was, on average, 35 min longer (Pr β>0 = .973) and light physical activity time 18 min shorter (Pr β>0 = .960) during the heat acclimation period. No differences were observed between conditions in sleep duration, subjective sleep quality, or moderate or vigorous physical activity. These findings may suggest that athletes and coaches need to be cognisant that heat acclimation training may alter sleep quality and increase sedentary behaviour.HighlightsFive consecutive days of heat training negatively affected some objective measures of sleep quality and incidental physical activity in recreationally trained athletes.Athletes and coaches need to be aware of the potential unintended consequences of using heat acclimation on sleep behaviours.
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Affiliation(s)
- John O Osborne
- School of Sport Sciences, UiT The Arctic University of Norway, Tromsø, Norway
- School of Exercise and Nutrition Sciences, Queensland University of Technology, Brisbane, Australia
| | - Geoffrey M Minett
- School of Exercise and Nutrition Sciences, Queensland University of Technology, Brisbane, Australia
| | - Ian B Stewart
- School of Exercise and Nutrition Sciences, Queensland University of Technology, Brisbane, Australia
| | - Stewart Trost
- School of Exercise and Nutrition Sciences, Queensland University of Technology, Brisbane, Australia
- School of Human Movement and Nutrition Sciences, University of Queensland, Brisbane, Australia
| | - Christopher Drovandi
- School of Mathematical Sciences, Queensland University of Technology, Brisbane, Australia
- Centre for Data Science, Queensland University of Technology, Brisbane, Australia
| | - Joseph T Costello
- Extreme Environments Laboratory, School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Toby G Pavey
- School of Exercise and Nutrition Sciences, Queensland University of Technology, Brisbane, Australia
| | - David N Borg
- Australian Centre for Health Services Innovation and Centre for Healthcare Transformation, School of Public Health and Social Work, Queensland University of Technology, Brisbane, Australia
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14
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Kluin KJ, Mossner JM, Costello JT, Chou KL, Patil PG. Motor speech effects in subthalamic deep brain stimulation for Parkinson's disease. J Neurosurg 2022; 137:722-728. [PMID: 35090126 PMCID: PMC10193494 DOI: 10.3171/2021.12.jns211729] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 12/02/2021] [Indexed: 11/06/2022]
Abstract
OBJECTIVE A motor speech disorder or dysarthria commonly arises in patients with Parkinson's disease (PD). The impact of subthalamic nucleus (STN) deep brain stimulation (DBS) on motor speech and the potential of intraoperative motor speech testing to predict outcomes are unknown. This study examined 1) the types and prevalence of motor speech changes observed with STN DBS and their relation to the preoperative condition, 2) the ability of intraoperative testing to predict postoperative changes in motor speech, and 3) the spatial relationship between stimulation sites producing maximal motor improvement, as measured by the Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS), and maximal motor speech deterioration. METHODS Comprehensive preoperative, intraoperative, and postoperative motor speech/dysarthria evaluations were performed in consecutive patients with advanced idiopathic PD who underwent STN DBS surgery in the period from 2011 to 2016. Preoperative type of dysarthria and overall dysarthria severity rating along with intraoperative motor speech testing results were evaluated as predictors of postoperative change. Atlas-independent, fully individualized field modeling was used to identify stimulation sites associated with maximal MDS-UPDRS motor improvement and motor speech deterioration. RESULTS Forty-three patients with PD treated with STN DBS were prospectively studied. Improved MDS-UPDRS motor scores and worsened dysarthria were demonstrated by a subset of patients (16/43). Preoperative dysarthria characteristics did not predict postoperative deterioration. Intraoperative assessment of motor speech strongly predicted postoperative outcomes (OR 4.4, p = 0.02). Sites of maximal MDS-UPDRS motor improvement and worsened dysarthria were distinct. Worsened dysarthria was associated with capsular stimulation, anterior and ventral to the site of maximal MDS-UPDRS motor improvement. CONCLUSIONS The predictive reliability of intraoperative motor speech testing, together with the identification of distinct stimulation sites for motor speech impairment and improved MDS-UPDRS motor function, raise the possibility that DBS lead repositioning or reprogramming could reduce adverse effects on motor speech without impacting MDS-UPDRS motor outcomes in patients undergoing STN DBS.
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Affiliation(s)
| | | | | | | | - Parag G. Patil
- Neurology
- Neurosurgery
- Biomedical Engineering, University of Michigan, Ann Arbor, Michigan
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15
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Costello JT, Nason SR, An H, Lee J, Mender MJ, Temmar H, Wallace DM, Lim J, Willsey MS, Patil PG, Jang T, Phillips JD, Kim HS, Blaauw D, Chestek CA. A low-power communication scheme for wireless, 1000 channel brain-machine interfaces. J Neural Eng 2022; 19. [PMID: 35613546 DOI: 10.1088/1741-2552/ac7352] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 05/24/2022] [Indexed: 11/12/2022]
Abstract
OBJECTIVE Brain-machine interfaces (BMIs) have the potential to restore motor function but are currently limited by electrode count and long-term recording stability. These challenges may be solved through the use of free-floating "motes" which wirelessly transmit recorded neural signals, if power consumption can be kept within safe levels when scaling to thousands of motes. Here, we evaluated a pulse-interval modulation (PIM) communication scheme for infrared (IR)-based motes that aims to reduce the wireless data rate and system power consumption. APPROACH To test PIM's ability to efficiently communicate neural information, we simulated the communication scheme in a real-time closed-loop BMI with non-human primates. Additionally, we performed circuit simulations of an IR-based 1000-mote system to calculate communication accuracy and total power consumption. MAIN RESULTS We found that PIM at 1kb/s per channel maintained strong correlations with true firing rate and matched online BMI performance of a traditional wired system. Closed-loop BMI tests suggest that lags as small as 30 ms can have significant performance effects. Finally, unlike other IR communication schemes, PIM is feasible in terms of power, and neural data can accurately be recovered on a receiver using 3mW for 1000 channels. SIGNIFICANCE These results suggest that PIM-based communication could significantly reduce power usage of wireless motes to enable higher channel-counts for high-performance BMIs.
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Affiliation(s)
- Joseph T Costello
- Electrical and Computer Engineering, University of Michigan, 2800 Plymouth Rd, B10, Ann Arbor, Michigan, 48109-1382, UNITED STATES
| | - Samuel R Nason
- Biomedical Engineering, University of Michigan, 2800 Plymouth Rd B10, Ann Arbor, Michigan, 48109-1382, UNITED STATES
| | - Hyochan An
- Electrical and Computer Engineering, University of Michigan, 2800 Plymouth Rd B10, Ann Arbor, Michigan, 48109-1382, UNITED STATES
| | - Jungho Lee
- Electrical and Computer Engineering, University of Michigan, 2800 Plymouth Rd B10, Ann Arbor, Michigan, 48109-1382, UNITED STATES
| | - Matthew J Mender
- Biomedical Engineering, University of Michigan, 2800 Plymouth Rd B10, Ann Arbor, Michigan, 48109-1382, UNITED STATES
| | - Hisham Temmar
- Biomedical Engineering, University of Michigan, 2800 Plymouth Rd B10, Ann Arbor, Michigan, 48109-1382, UNITED STATES
| | - Dylan M Wallace
- Robotics Institute, University of Michigan, 2800 Plymouth Rd B10, Ann Arbor, 48109-1382, UNITED STATES
| | - Jongyup Lim
- Electrical and Computer Engineering, University of Michigan, 2800 Plymouth Rd B10, Ann Arbor, Michigan, 48109-1382, UNITED STATES
| | - Matthew S Willsey
- Department of Neurosurgery, University of Michigan Medical School, 1500 E Medical Center Drive, Ann Arbor, 48109-0624, UNITED STATES
| | - Parag G Patil
- Neurosurgery, University of Michigan, 1500 E Medical Center Drive, Ann Arbor, Michigan, 48109, UNITED STATES
| | - Taekwang Jang
- Department of Information Technology and Electrical Engineering, ETH Zurich, ETH Zurich, Rämistrasse 101, Zurich, 8092, SWITZERLAND
| | - Jamie Dean Phillips
- Department of Electrical and Computer Engineering, University of Delaware, Evans Hall, 139 The Green,, Newark, Delaware, 19716-5600, UNITED STATES
| | - Hun-Seok Kim
- Electrical and Computer Engineering, University of Michigan, 2800 Plymouth Rd B10, Ann Arbor, Michigan, 48109-1382, UNITED STATES
| | - David Blaauw
- University of Michigan, 2800 Plymouth Rd B10, Ann Arbor, Michigan, 48109-1382, UNITED STATES
| | - Cynthia A Chestek
- Biomedical Engineering, University of Michigan, 2800 Plymouth Rd B10, Ann Arbor, Michigan, 48109-1382, UNITED STATES
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16
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Lim J, Lee J, Moon E, Barrow M, Atzeni G, Letner JG, Costello JT, Nason SR, Patel PR, Sun Y, Patil PG, Kim HS, Chestek CA, Phillips J, Blaauw D, Sylvester D, Jang T. A Light-Tolerant Wireless Neural Recording IC for Motor Prediction With Near-Infrared-Based Power and Data Telemetry. IEEE J Solid-State Circuits 2022; 57:1061-1074. [PMID: 36186085 PMCID: PMC9518712 DOI: 10.1109/jssc.2022.3141688] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Miniaturized and wireless near-infrared (NIR) based neural recorders with optical powering and data telemetry have been introduced as a promising approach for safe long-term monitoring with the smallest physical dimension among state-of-the-art standalone recorders. However, a main challenge for the NIR based neural recording ICs is to maintain robust operation in the presence of light-induced parasitic short circuit current from junction diodes. This is especially true when the signal currents are kept small to reduce power consumption. In this work, we present a light-tolerant and low-power neural recording IC for motor prediction that can fully function in up to 300 μW/mm2 of light exposure. It achieves best-in-class power consumption of 0.57 μW at 38° C with a 4.1 NEF pseudo-resistorless amplifier, an on-chip neural feature extractor, and individual mote level gain control. Applying the 20-channel pre-recorded neural signals of a monkey, the IC predicts finger position and velocity with correlation coefficient up to 0.870 and 0.569, respectively, with individual mote level gain control enabled. In addition, wireless measurement is demonstrated through optical power and data telemetry using a custom PV/LED GaAs chip wire bonded to the proposed IC.
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Affiliation(s)
- Jongyup Lim
- Department of Electrical and Computer Engineering, University of Michigan, Ann Arbor, MI, 48109 USA
| | - Jungho Lee
- Department of Electrical and Computer Engineering, University of Michigan, Ann Arbor, MI, 48109 USA
| | - Eunseong Moon
- Department of Electrical and Computer Engineering, University of Michigan, Ann Arbor, MI, 48109 USA
| | - Michael Barrow
- Department of Electrical and Computer Engineering, University of Michigan, Ann Arbor, MI, 48109 USA
| | - Gabriele Atzeni
- Department of Information Technology and Electrical Engineering, ETH Zürich, 8092 Zürich, Switzerland
| | - Joseph G Letner
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, 48109 USA
| | - Joseph T Costello
- Department of Electrical and Computer Engineering, University of Michigan, Ann Arbor, MI, 48109 USA
| | - Samuel R Nason
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, 48109 USA
| | - Paras R Patel
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, 48109 USA
| | - Yi Sun
- Department of Electrical and Computer Engineering, University of Michigan, Ann Arbor, MI, 48109 USA
| | - Parag G Patil
- Department of Neurological Surgery, Neurology, Anesthesiology, and Biomedical Engineering, University of Michigan, Ann Arbor, MI, 48109 USA
| | - Hun-Seok Kim
- Department of Electrical and Computer Engineering, University of Michigan, Ann Arbor, MI, 48109 USA
| | - Cynthia A Chestek
- Department of Biomedical Engineering and Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, MI, 48109 USA
| | - Jamie Phillips
- Department of Electrical and Computer Engineering, University of Delaware, Newark, DE 19716 USA
| | - David Blaauw
- Department of Electrical and Computer Engineering, University of Michigan, Ann Arbor, MI, 48109 USA
| | - Dennis Sylvester
- Department of Electrical and Computer Engineering, University of Michigan, Ann Arbor, MI, 48109 USA
| | - Taekwang Jang
- Department of Information Technology and Electrical Engineering, ETH Zürich, 8092 Zürich, Switzerland
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17
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Ando S, Komiyama T, Tanoue Y, Sudo M, Costello JT, Uehara Y, Higaki Y. Cognitive Improvement After Aerobic and Resistance Exercise Is Not Associated With Peripheral Biomarkers. Front Behav Neurosci 2022; 16:853150. [PMID: 35368295 PMCID: PMC8967356 DOI: 10.3389/fnbeh.2022.853150] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 02/21/2022] [Indexed: 02/02/2023] Open
Abstract
The role of peripheral biomarkers following acute physical exercise on cognitive improvement has not been systematically evaluated. This study aimed to explore the role of peripheral circulating biomarkers in executive performance following acute aerobic and resistance exercise. Nineteen healthy males completed a central executive (Go/No-Go) task before and after 30-min of perceived intensity matched aerobic and resistance exercise. In the aerobic condition, the participants cycled an ergometer at 40% peak oxygen uptake. In the resistance condition, they performed resistance exercise using elastic bands. Before and after an acute bout of physical exercise, venous samples were collected for the assessment of following biomarkers: adrenaline, noradrenaline, glucose, lactate, cortisol, insulin-like growth hormone factor 1, and brain-derived neurotrophic factor. Reaction time decreased following both aerobic exercise and resistance exercise (p = 0.04). Repeated measures correlation analysis indicated that changes in reaction time were not associated with the peripheral biomarkers (all p > 0.05). Accuracy tended to decrease in the resistance exercise condition (p = 0.054). Accuracy was associated with changes in adrenaline [rrm(18) = −0.51, p = 0.023], noradrenaline [rrm(18) = −0.66, p = 0.002], lactate [rrm(18) = −0.47, p = 0.035], and brain-derived neurotrophic factor [rrm(17) = −0.47, p = 0.044] in the resistance condition. These findings suggest that these peripheral biomarkers do not directly contribute to reduction in reaction time following aerobic or resistance exercise. However, greater sympathoexcitation, reflected by greater increase in noradrenaline, may be associated with a tendency for a reduction in accuracy after acute resistance exercise.
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Affiliation(s)
- Soichi Ando
- Graduate School of Informatics and Engineering, The University of Electro-Communications, Chofu, Japan
- *Correspondence: Soichi Ando,
| | - Takaaki Komiyama
- Center for Education in Liberal Arts and Sciences, Osaka University, Osaka, Japan
| | - Yukiya Tanoue
- Graduate School of Sports and Health Science, Fukuoka University, Fukuoka, Japan
| | - Mizuki Sudo
- Physical Fitness Research Institute, Meiji Yasuda Life Foundation of Health and Welfare, Shinjuku City, Japan
| | - Joseph T. Costello
- Extreme Environments Laboratory, School of Sport, Health & Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Yoshinari Uehara
- Faculty of Sports and Health Science, Fukuoka University, Fukuoka, Japan
| | - Yasuki Higaki
- Faculty of Sports and Health Science, Fukuoka University, Fukuoka, Japan
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18
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Al Rajeh A, Bhogal AS, Zhang Y, Costello JT, Hurst JR, Mani AR. Application of oxygen saturation variability analysis for the detection of exacerbation in individuals with COPD: A proof-of-concept study. Physiol Rep 2021; 9:e15132. [PMID: 34851045 PMCID: PMC8634631 DOI: 10.14814/phy2.15132] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 10/30/2021] [Accepted: 11/13/2021] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Individuals with chronic obstructive pulmonary disease (COPD) commonly experience exacerbations, which may require hospital admission. Early detection of exacerbations, and therefore early treatment, could be crucial in preventing admission and improving outcomes. Our previous research has demonstrated that the pattern analysis of peripheral oxygen saturation (Sp O2 ) fluctuations provides novel insights into the engagement of the respiratory control system in response to physiological stress (hypoxia). Therefore, this pilot study tested the hypothesis that the pattern of Sp O2 variations in overnight recordings of individuals with COPD would distinguish between stable and exacerbation phases of the disease. METHODS Overnight pulse oximetry data from 11 individuals with COPD, who exhibited exacerbation after a period of stable disease, were examined. Stable phase recordings were conducted overnight and one night prior to exacerbation recordings were also analyzed. Pattern analysis of Sp O2 variations was carried examined using sample entropy (for assessment of irregularity), the multiscale entropy (complexity), and detrended fluctuation analysis (self-similarity). RESULTS Sp O2 variations displayed a complex pattern in both stable and exacerbation phases of COPD. During an exacerbation, Sp O2 entropy increased (p = 0.029) and long-term fractal-like exponent (α2) decreased (p = 0.002) while the mean and standard deviation of Sp O2 time series remained unchanged. Through ROC analyses, Sp O2 entropy and α2 were both able to classify the COPD phases into either stable or exacerbation phase. With the best positive predictor value (PPV) for sample entropy (PPV = 70%) and a cut-off value of 0.454. While the best negative predictor value (NPV) was α2 (NPV = 78%) with a cut-off value of 1.00. CONCLUSION Alterations in Sp O2 entropy and the fractal-like exponent have the potential to detect exacerbations in COPD. Further research is warranted to examine if Sp O2 variability analysis could be used as a novel objective method of detecting exacerbations.
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Affiliation(s)
- Ahmed Al Rajeh
- UCL RespiratoryRoyal Free CampusDivision of MedicineUniversity College LondonLondonUK
- Department of Respiratory CareKing Faisal UniversityAl‐AhsaSaudi Arabia
| | - Amar S. Bhogal
- Network Physiology LaboratoryDivision of MedicineUCLLondonUK
- Medical SchoolUniversity of BirminghamBirminghamUK
| | - Yunkai Zhang
- Network Physiology LaboratoryDivision of MedicineUCLLondonUK
| | - Joseph T. Costello
- Extreme Environment LaboratorySchool of Sport, Health and Exercise ScienceUniversity of PortsmouthPortsmouthUK
| | - John R Hurst
- UCL RespiratoryRoyal Free CampusDivision of MedicineUniversity College LondonLondonUK
| | - Ali R. Mani
- Network Physiology LaboratoryDivision of MedicineUCLLondonUK
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19
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Costello JT, Corbett J. The inaugural 'Mid-Career Researcher' prize: Rewarding and acknowledging future leaders in physiology. Exp Physiol 2021; 107:1-2. [PMID: 34783407 DOI: 10.1113/ep090024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 11/09/2021] [Indexed: 11/08/2022]
Affiliation(s)
- Joseph T Costello
- Extreme Environments Laboratory, School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, UK
| | - Jo Corbett
- Extreme Environments Laboratory, School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, UK
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20
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Costello JT, Wilkes M, Tipton MJ. From pigeon holes to descending spirals: a paradigm of physiology, cognitive performance and behaviour in extreme environments. Exp Physiol 2021; 106:1863-1864. [PMID: 34288179 DOI: 10.1113/ep089938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 07/16/2021] [Indexed: 11/08/2022]
Affiliation(s)
- Joseph T Costello
- Extreme Environments Laboratory, School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, UK
| | - Matthew Wilkes
- Extreme Environments Laboratory, School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, UK.,Current Health Ltd, Edinburgh, UK
| | - Michael J Tipton
- Extreme Environments Laboratory, School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, UK
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21
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Minett GM, Skein M, Bieuzen F, Stewart IB, Borg DN, Bach AJE, Costello JT. Heat acclimation for protection from exertional heat stress. Hippokratia 2021. [DOI: 10.1002/14651858.cd012016.pub2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Geoffrey M Minett
- School of Exercise and Nutrition Sciences and Institute of Health and Biomedical Innovation; Queensland University of Technology; Brisbane Australia
| | - Melissa Skein
- School of Human Movement Studies; Charles Sturt University; Bathurst Australia
| | | | - Ian B Stewart
- School of Exercise and Nutrition Sciences and Institute of Health and Biomedical Innovation; Queensland University of Technology; Brisbane Australia
| | - David N Borg
- School of Exercise and Nutrition Sciences and Institute of Health and Biomedical Innovation; Queensland University of Technology; Brisbane Australia
| | - Aaron JE Bach
- School of Exercise and Nutrition Sciences and Institute of Health and Biomedical Innovation; Queensland University of Technology; Brisbane Australia
| | - Joseph T Costello
- Department of Sport and Exercise Science; University of Portsmouth; Portsmouth UK
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22
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Corbett J, Massey HC, Costello JT, Tipton MJ, Neal RA. The effect of medium-term heat acclimation on endurance performance in a temperate environment. Eur J Sport Sci 2021; 22:190-199. [PMID: 33241974 DOI: 10.1080/17461391.2020.1856935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
We investigated whether an 11-day heat acclimation programme (HA) enhanced endurance performance in a temperate environment, and the mechanisms underpinning any ergogenic effect. Twenty-four males (V̇O2max: 56.7 ± 7.5 mL·kg-1·min-1) completed either: (i) HA consisting of 11 consecutive daily exercise sessions (60-90 min·day-1; n = 16) in a hot environment (40°C, 50% RH) or; (ii) duration and exertion matched exercise in cool conditions (CON; n = 8 [11°C, 60% RH]). Before and after each programme power at lactate threshold, mechanical efficiency, VO2max, peak power output (PPO) and work done during a 30-minute cycle trial (T30) were determined under temperate conditions (22°C, 50% RH). HA reduced resting (-0.34 ± 0.30°C) and exercising (-0.43 ± 0.30°C) rectal temperature, and increased whole-body sweating (+0.37 ± 0.31 L·hr-1) (all P≤0.001), with no change in CON. Plasma volume increased in HA (10.1 ± 7.2%, P < 0.001) and CON (7.2 ± 6.3%, P = 0.015) with no between-groups difference, whereas exercise heart rate reduced in both groups, but to a greater extent in HA (-20 ± 11 b·min-1) than CON (-6 ± 4 b·min-1). VO2max, lactate threshold and mechanical efficiency were unaffected by HA. PPO increased in both groups (+14 ± 18W), but this was not related to alterations in any of the performance or thermal variables, and T30 performance was unchanged in either group (HA: Pre = 417 ± 90 vs. Post = 427 ± 83 kJ; CON: Pre = 418 ± 63 vs. Post = 423 ± 56 kJ). In conclusion, 11-days HA induces thermophysiological adaptations, but does not alter the key determinants of endurance performance. In trained males, the effect of HA on endurance performance in temperate conditions is no greater than that elicited by exertion and duration matched exercise training in cool conditions.
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Affiliation(s)
- Jo Corbett
- Extreme Environments Laboratory, School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, UK
| | - Heather C Massey
- Extreme Environments Laboratory, School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, UK
| | - Joseph T Costello
- Extreme Environments Laboratory, School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, UK
| | - Michael J Tipton
- Extreme Environments Laboratory, School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, UK
| | - Rebecca A Neal
- Department of Rehabilitation and Sport Sciences, Bournemouth University, Poole, UK
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23
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Malaga KA, Costello JT, Chou KL, Patil PG. Atlas-independent, N-of-1 tissue activation modeling to map optimal regions of subthalamic deep brain stimulation for Parkinson disease. Neuroimage Clin 2020; 29:102518. [PMID: 33333464 PMCID: PMC7736726 DOI: 10.1016/j.nicl.2020.102518] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 11/25/2020] [Accepted: 11/27/2020] [Indexed: 01/13/2023]
Abstract
Neuroanatomical variations among patients are obscured in atlas-based VTA modeling. N-of-1 neuroanatomical and VTA modeling enables patient-level precision. Mean optimal stimulation is dorsomedial to the STN, near its posterior half. Individual VTAs deviate from optimal stimulation sites to varying degrees. Optimal stimulation sites for rigidity, bradykinesia, and tremor partially overlap.
Background Motor outcomes after subthalamic deep brain stimulation (STN DBS) for Parkinson disease (PD) vary considerably among patients and strongly depend on stimulation location. The objective of this retrospective study was to map the regions of optimal STN DBS for PD using an atlas-independent, fully individualized (N-of-1) tissue activation modeling approach and to assess the relationship between patient-level therapeutic volumes of tissue activation (VTAs) and motor improvement. Methods The stimulation-induced electric field for 40 PD patients treated with bilateral STN DBS was modeled using finite element analysis. Neurostimulation models were generated for each patient, incorporating their individual STN anatomy, DBS lead position and orientation, anisotropic tissue conductivity, and clinical stimulation settings. A voxel-based analysis of the VTAs was then used to map the optimal location of stimulation. The amount of stimulation in specific regions relative to the STN was measured and compared between STNs with more and less optimal stimulation, as determined by their motor improvement scores and VTA. The relationship between VTA location and motor outcome was then assessed using correlation analysis. Patient variability in terms of STN anatomy, active contact position, and VTA location were also evaluated. Results from the N-of-1 model were compared to those from a simplified VTA model. Results Tissue activation modeling mapped the optimal location of stimulation to regions medial, posterior, and dorsal to the STN centroid. These regions extended beyond the STN boundary towards the caudal zona incerta (cZI). The location of the VTA and active contact position differed significantly between STNs with more and less optimal stimulation in the dorsal-ventral and anterior-posterior directions. Therapeutic stimulation spread noticeably more in the dorsal and posterior directions, providing additional evidence for cZI as an important DBS target. There were significant linear relationships between the amount of dorsal and posterior stimulation, as measured by the VTA, and motor improvement. These relationships were more robust than those between active contact position and motor improvement. There was high variability in STN anatomy, active contact position, and VTA location among patients. Spherical VTA modeling was unable to reproduce these results and tended to overestimate the size of the VTA. Conclusion Accurate characterization of the spread of stimulation is needed to optimize STN DBS for PD. High variability in neuroanatomy, stimulation location, and motor improvement among patients highlights the need for individualized modeling techniques. The atlas-independent, N-of-1 tissue activation modeling approach presented in this study can be used to develop and evaluate stimulation strategies to improve clinical outcomes on an individual basis.
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Affiliation(s)
- Karlo A Malaga
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Joseph T Costello
- Department of Electrical Engineering, University of Michigan, Ann Arbor, MI, USA
| | - Kelvin L Chou
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA; Department of Neurosurgery, University of Michigan, Ann Arbor, MI, USA
| | - Parag G Patil
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, USA; Department of Neurology, University of Michigan, Ann Arbor, MI, USA; Department of Neurosurgery, University of Michigan, Ann Arbor, MI, USA.
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24
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Komiyama T, Tanoue Y, Sudo M, Costello JT, Uehara Y, Higaki Y, Ando S. Cognitive Impairment during High-Intensity Exercise: Influence of Cerebral Blood Flow. Med Sci Sports Exerc 2020; 52:561-568. [PMID: 31609297 DOI: 10.1249/mss.0000000000002183] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
PURPOSE Cognitive performance appears to be impaired during high-intensity exercise, and this occurs concurrently with a reduction in cerebral blood flow (CBF). However, it is unclear whether cognitive impairment during high-intensity exercise is associated with reduced CBF. We tested the hypothesis that a reduction in CBF is responsible for impaired cognitive performance during high-intensity exercise. METHODS Using a randomized crossover design 17 healthy males performed spatial delayed response and Go/No-Go tasks in three conditions (exercise [EX], exercise+CO2 [EX+CO2], and a nonexercising control [CON]). In the EX and EX+CO2, they performed cognitive tasks at rest and during 8 min of moderate and high-intensity exercise. Exercise intensity corresponded to ~50% (moderate) and ~80% (high) of peak oxygen uptake. In the EX+CO2, the participants inspired hypercapnic gas (2% CO2) during high-intensity exercise. In the CON, they performed the cognitive tasks without exercise. RESULTS Middle cerebral artery mean velocity increased during high-intensity exercise in the EX+CO2 relative to the EX (69.4 [10.6] cm·s, vs 57.2 [7.7] cm·s, P < 0.001). Accuracy of the cognitive tasks was impaired during high-intensity exercise in the EX (84.1% [13.3%], P < 0.05) and the EX+ CO2 (85.7 [11.6%], P < 0.05) relative to rest (EX: 95.1% [5.3%], EX+CO2: 95.1 [5.3%]). However, no differences between the EX and the EX+CO2 were observed (P > 0.10). These results demonstrate that restored CBF did not prevent cognitive impairment during high-intensity exercise. CONCLUSIONS We conclude that a reduction in CBF is not responsible for impaired cognitive performance during high-intensity exercise.
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Affiliation(s)
| | - Yukiya Tanoue
- Graduate School of Sports and Health Science, Fukuoka University, Fukuoka, JAPAN
| | - Mizuki Sudo
- Meiji Yasuda Life Foundation of Health and Welfare, Tokyo, JAPAN
| | - Joseph T Costello
- Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, Portsmouth, UNITED KINGDOM
| | | | - Yasuki Higaki
- Faculty of Sports Science, Fukuoka University, Fukuoka, JAPAN
| | - Soichi Ando
- Graduate School of Informatics and Engineering, The University of Electro-Communications, Tokyo, JAPAN
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25
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Jiang Y, Costello JT, Williams TB, Panyapiean N, Bhogal AS, Tipton MJ, Corbett J, Mani AR. A network physiology approach to oxygen saturation variability during normobaric hypoxia. Exp Physiol 2020; 106:151-159. [DOI: 10.1113/ep088755] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 07/02/2020] [Indexed: 02/02/2023]
Affiliation(s)
- Yuji Jiang
- Network Physiology Laboratory UCL Division of Medicine University College London London UK
| | - Joseph T. Costello
- Extreme Environments Laboratory School of Sport, Health and Exercise Science University of Portsmouth Portsmouth UK
| | - Thomas B. Williams
- Extreme Environments Laboratory School of Sport, Health and Exercise Science University of Portsmouth Portsmouth UK
| | - Nawamin Panyapiean
- Network Physiology Laboratory UCL Division of Medicine University College London London UK
| | - Amar S. Bhogal
- Network Physiology Laboratory UCL Division of Medicine University College London London UK
| | - Michael J. Tipton
- Extreme Environments Laboratory School of Sport, Health and Exercise Science University of Portsmouth Portsmouth UK
| | - Jo Corbett
- Extreme Environments Laboratory School of Sport, Health and Exercise Science University of Portsmouth Portsmouth UK
| | - Ali R. Mani
- Network Physiology Laboratory UCL Division of Medicine University College London London UK
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26
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Eglin CM, Costello JT, Tipton MJ, Massey H. Previous recreational cold exposure does not alter endothelial function or sensory thermal thresholds in the hands or feet. Exp Physiol 2020; 106:328-337. [DOI: 10.1113/ep088555] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Accepted: 05/04/2020] [Indexed: 01/03/2023]
Affiliation(s)
- Clare M. Eglin
- Extreme Environments Laboratory School of Sport Health and Exercise Science University of Portsmouth Portsmouth UK
| | - Joseph T. Costello
- Extreme Environments Laboratory School of Sport Health and Exercise Science University of Portsmouth Portsmouth UK
| | - Michael J. Tipton
- Extreme Environments Laboratory School of Sport Health and Exercise Science University of Portsmouth Portsmouth UK
| | - Heather Massey
- Extreme Environments Laboratory School of Sport Health and Exercise Science University of Portsmouth Portsmouth UK
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27
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Costello JT, Bhogal AS, Williams TB, Bekoe R, Sabir A, Tipton MJ, Corbett J, Mani AR. Effects of Normobaric Hypoxia on Oxygen Saturation Variability. High Alt Med Biol 2020; 21:76-83. [PMID: 32069121 DOI: 10.1089/ham.2019.0092] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Background: The study is the first to evaluate the effects of graded normobaric hypoxia on SpO2 variability in healthy individuals. Materials and Methods: Twelve healthy males (mean [standard deviation] age 22 [4] years) were exposed to four simulated environments (fraction of inspired oxygen [FIO2]: 0.12, 0.145, 0.17, and 0.21) for 45 minutes, in a balanced crossover design. Results: Sample entropy, a tool that quantifies the irregularity of pulse oximetry fluctuations, was used as a measure of SpO2 variability. SpO2 entropy increased as the FIO2 decreased, and there was a strong significant negative correlation between mean SpO2 and its entropy during hypoxic exposure (r = -0.841 to -0.896, p < 0.001). In addition, SpO2 sample entropy, but not mean SpO2, was correlated (r = 0.630-0.760, p < 0.05) with dyspnea in FIO2 0.17, 0.145, and 0.12 and importantly, SpO2 sample entropy at FIO2 0.17 was correlated with dyspnea at FIO2 0.145 (r = 0.811, p < 0.01). Conclusions: These findings suggest that SpO2 variability analysis may have the potential to be used in a clinical setting as a noninvasive measure to identify the negative sequelae of hypoxemia.
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Affiliation(s)
- Joseph T Costello
- Extreme Environments Laboratory, School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Amar S Bhogal
- Network Physiology Laboratory, UCL Division of Medicine, University College London, London, United Kingdom
| | - Thomas B Williams
- Extreme Environments Laboratory, School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Richard Bekoe
- Network Physiology Laboratory, UCL Division of Medicine, University College London, London, United Kingdom
| | - Amin Sabir
- Network Physiology Laboratory, UCL Division of Medicine, University College London, London, United Kingdom
| | - Michael J Tipton
- Extreme Environments Laboratory, School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Jo Corbett
- Extreme Environments Laboratory, School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Ali R Mani
- Network Physiology Laboratory, UCL Division of Medicine, University College London, London, United Kingdom
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28
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Causer AJ, Shute JK, Cummings MH, Shepherd AI, Gruet M, Costello JT, Bailey S, Lindley M, Pearson C, Connett G, Allenby MI, Carroll MP, Daniels T, Saynor ZL. Circulating biomarkers of antioxidant status and oxidative stress in people with cystic fibrosis: A systematic review and meta-analysis. Redox Biol 2020; 32:101436. [PMID: 32044291 PMCID: PMC7264436 DOI: 10.1016/j.redox.2020.101436] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Revised: 01/14/2020] [Accepted: 01/16/2020] [Indexed: 02/03/2023] Open
Abstract
Introduction Oxidative stress may play an important role in the pathophysiology of cystic fibrosis (CF). This review aimed to quantify CF-related redox imbalances. Methods Systematic searches of the Medline, CINAHL, CENTRAL and PsycINFO databases were conducted. Mean content of blood biomarkers from people with clinically-stable CF and non-CF controls were used to calculate the standardized mean difference (SMD) and 95% confidence intervals (95% CI). Results Forty-nine studies were eligible for this review including a total of 1792 people with CF and 1675 controls. Meta-analysis revealed that protein carbonyls (SMD: 1.13, 95% CI: 0.48 to 1.77), total F2-isoprostane 8-iso-prostaglandin F2α (SMD: 0.64, 95% CI: 0.23 to 1.05) and malondialdehyde (SMD: 1.34, 95% CI: 0.30 to 2.39) were significantly higher, and vitamins A (SMD: −0.66, 95% CI -1.14 to −0.17) and E (SMD: −0.74, 95% CI: −1.28 to −0.20), β-carotene (SMD: −1.80, 95% CI: −2.92 to −0.67), lutein (SMD: −1.52, 95% CI: −1.83 to −1.20) and albumin (SMD: −0.98, 95% CI: −1.68 to −0.27) were significantly lower in the plasma or serum of people with CF versus controls. Conclusions This systematic review and meta-analysis found good evidence for reduced antioxidant capacity and elevated oxidative stress in people with clinically-stable CF. Blood biomarkers of oxidative stress were elevated in stable CF vs non-CF controls. Lipid peroxidation was positively correlated with age and immune cell count in CF. Antioxidants vitamins A & E, β-carotene, lutein and albumin were lower in stable CF. Antioxidants were positively correlated with body mass index and lung function in CF.
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Affiliation(s)
- Adam J Causer
- School of Sport, Health and Exercise Science, Faculty of Science and Health, University of Portsmouth, Portsmouth, UK; Cystic Fibrosis Unit, University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - Janis K Shute
- School of Pharmacy and Biomedical Sciences, Faculty of Science and Health, University of Portsmouth, Portsmouth, UK
| | - Michael H Cummings
- Department of Diabetes and Endocrinology, Queen Alexandra Hospital, Portsmouth, UK
| | - Anthony I Shepherd
- School of Sport, Health and Exercise Science, Faculty of Science and Health, University of Portsmouth, Portsmouth, UK
| | - Mathieu Gruet
- Laboratory of Impact of Physical Activity on Health (IAPS), UR n°201723207F, University of Toulon, France
| | - Joseph T Costello
- School of Sport, Health and Exercise Science, Faculty of Science and Health, University of Portsmouth, Portsmouth, UK
| | - Stephen Bailey
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Martin Lindley
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Clare Pearson
- Cystic Fibrosis Unit, University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - Gary Connett
- National Institute for Health Research, Southampton Biomedical Research Centre, Southampton Children's Hospital, Southampton, UK
| | - Mark I Allenby
- Cystic Fibrosis Unit, University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - Mary P Carroll
- Cystic Fibrosis Unit, University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - Thomas Daniels
- Cystic Fibrosis Unit, University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | - Zoe L Saynor
- School of Sport, Health and Exercise Science, Faculty of Science and Health, University of Portsmouth, Portsmouth, UK; Cystic Fibrosis Unit, University Hospital Southampton NHS Foundation Trust, Southampton, UK.
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29
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Borg DN, Osborne JO, Stewart IB, Costello JT, Headrick J, McMaster BS, Borg SJ, Minett GM. The availability of task-specific feedback does not affect 20 km time trial cycling performance or test-retest reliability in trained cyclists. J Sci Med Sport 2020; 23:758-763. [PMID: 31892509 DOI: 10.1016/j.jsams.2019.12.024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Revised: 12/13/2019] [Accepted: 12/17/2019] [Indexed: 11/30/2022]
Abstract
OBJECTIVES This study examined the influence of the availability of task-specific feedback on 20 km time trial (20TT) cycling performance and test-retest reliability. DESIGN Thirty trained, club-level cyclists completed two 20TT's on different days, with (feedback, FB) or without (no-feedback, NFB) task-specific feedback (i.e., power output, cadence, gear and heart rate [HR]). Elapsed distance was provided in both conditions. METHODS During trials, ergometer variables and HR were continuously recorded, and a rating of perceived exertion (RPE) was collected every 2 km. Data were analysed using linear mixed-effects models in a Bayesian framework, and Cohen's d was calculated for standardised differences. The reliability of finish time and mean power output (PO) was determined via multiple indices, including intraclass correlations (ICC). RESULTS Performance, pacing behaviour, and RPE were not statistically different between conditions. The posterior mean difference [95% credible interval] between TT1 and TT2 for FB and NFB was 10s [-5, 25] and -2s [-17, 14], respectively. In TT2, HR was statistically higher (∼8bmin-1) in FB compared to NFB after 13 km (d = 2.08-2.25). However, this result was explained by differences in maximal HR. Finish time (FB: ICC= 0.99; NFB: ICC=0.99) and mean power output (FB: ICC=0.99; NFB: ICC=0.99) in each condition were substantially reliable. CONCLUSIONS The availability of task-specific information did not affect 20TT performance or reliability. Except for elapsed distance, task-specific feedback should be withheld from trained cyclists when evaluating interventions that may affect performance, to prevent participants from recalling previous performance settings.
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Affiliation(s)
- David N Borg
- Institute of Health and Biomedical Innovation, School of Exercise and Nutrition Sciences, Queensland University of Technology, Australia; The Hopkins Centre, Menzies Health Institute Queensland, Griffith University, Australia.
| | - John O Osborne
- Institute of Health and Biomedical Innovation, School of Exercise and Nutrition Sciences, Queensland University of Technology, Australia
| | - Ian B Stewart
- Institute of Health and Biomedical Innovation, School of Exercise and Nutrition Sciences, Queensland University of Technology, Australia
| | - Joseph T Costello
- Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, United Kingdom
| | | | - Benjamin S McMaster
- Institute of Health and Biomedical Innovation, School of Exercise and Nutrition Sciences, Queensland University of Technology, Australia
| | - Samantha J Borg
- The Hopkins Centre, Menzies Health Institute Queensland, Griffith University, Australia; Centre for Health System Reform and Integration, University of Queensland-Mater Research Institute, Australia
| | - Geoffrey M Minett
- Institute of Health and Biomedical Innovation, School of Exercise and Nutrition Sciences, Queensland University of Technology, Australia
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30
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Krueger M, Costello JT, Stenzel M, Mester J, Wahl P. The physiological effects of daily cold-water immersion on 5-day tournament performance in international standard youth field-hockey players. Eur J Appl Physiol 2019; 120:295-305. [PMID: 31797035 DOI: 10.1007/s00421-019-04274-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 11/26/2019] [Indexed: 12/01/2022]
Abstract
PURPOSE This study examined the effects of daily post-exercise cold-water immersion (CWI) on match performance, perceptual recovery, and biomarkers of muscle damage and metabolic load during a 5-day international tournament of elite youth field-hockey players. METHODS The entire German under-18 national squad (n = 18) was randomly assigned to a daily CWI- (5-min at ~ 6 °C; excluding the head; n = 9) or passive recovery (CON; n = 9) intervention. Training and match performance were assessed using a GPS-tracking system and perceived exertion (RPE). Daily ratings of delayed onset muscle soreness (DOMS), perceived stress and recovery, quality of sleep, heart-rate recovery and serum creatine kinase (CK), lactate dehydrogenase, and urea nitrogen were also recorded. Repeated-sprint ability (RSA) and counter-movement jump (CMJ) were carried out on days 1 and 5. RESULTS There was no significance between intervention differences in time-on pitch, total distance, velocity zones, and accelerometer-base parameters during match performance (all p > 0.05). DOMS (p < 0.01), RPE (p < 0.01), and CK (p < 0.01) were significantly elevated over the course of the tournament; however, no between-intervention effects were observed (all p > 0.05). Both groups were able to maintain RSA and CMJ (all p > 0.05). CONCLUSION In conclusion, daily post-exercise CWI did not improve match performance, perceptual recovery, or biomarkers of muscle damage and metabolic load in elite youth field-hockey players.
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Affiliation(s)
- Malte Krueger
- Department of Preventative and Rehabilitative Sports and Performance Medicine, Institute of Cardiology and Sports Medicine, German Sport University Cologne, Cologne, Germany. .,The German Research Centre of Elite Sport, German Sport University Cologne, Cologne, Germany.
| | - Joseph T Costello
- Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, Portsmouth, UK
| | - Mirko Stenzel
- The German Research Centre of Elite Sport, German Sport University Cologne, Cologne, Germany.,German Hockey Federation, Mönchengladbach, Germany
| | - Joachim Mester
- The German Research Centre of Elite Sport, German Sport University Cologne, Cologne, Germany
| | - Patrick Wahl
- The German Research Centre of Elite Sport, German Sport University Cologne, Cologne, Germany.,Department of Molecular and Cellular Sports Medicine, Institute of Cardiology and Sports Medicine, German Sport University Cologne, Cologne, Germany
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31
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Hohenauer E, Costello JT, Deliens T, Clarys P, Stoop R, Clijsen R. Partial-body cryotherapy (-135°C) and cold-water immersion (10°C) after muscle damage in females. Scand J Med Sci Sports 2019; 30:485-495. [PMID: 31677292 PMCID: PMC7027844 DOI: 10.1111/sms.13593] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 09/05/2019] [Accepted: 10/28/2019] [Indexed: 12/12/2022]
Abstract
This randomized controlled trial examined the effects of cold‐water immersion (CWI), partial‐body cryotherapy (PBC), or a passive control (CON) on physiological and recovery variables following exercise‐induced muscle damage (EIMD, 5 × 20 drop jumps) in females. Twenty‐eight females were allocated to PBC (30 seconds at −60°C, 2 minutes at −135°C), CWI (10 minutes at 10°C), or CON (10 minutes resting). Muscle oxygen saturation (SmO2), cutaneous vascular conductance (CVC), mean arterial pressure (MAP), and local skin temperature were assessed at baseline and through 60 minutes (10‐minute intervals), while delayed onset of muscle soreness (DOMS), muscle swelling, maximum voluntary isometric contraction (MVIC), and vertical jump performance (VJP) were assessed up to 72 hours (24‐hour intervals) following treatments. SmO2 was lower in PBC (Δ‐2.77 ± 13.08%) and CWI (Δ‐5.91 ± 11.80%) compared with CON (Δ18.96 ± 1.46%) throughout the 60‐minute follow‐up period (P < .001). CVC was lower from PBC (92.7 ± 25.0%, 90.5 ± 23.4%) and CWI (90.3 ± 23.5%, 88.1 ± 22.9%) compared with CON (119.0 ± 5.1 and 116.1 ± 6.6%, respectively) between 20 and 30 minutes (P < .05). Mean skin temperature was lower from CWI vs PBC (between 10 and 40 minutes, P < .05). Mean skin temperature was higher in CON compared with CWI up to 60 minutes and compared with PBC up to 30 minutes (P < .05). DOMS was lower following both PBC and CWI compared with CON through 72‐hour (P < .05), with no difference between groups. No main group differences for swelling, MVIC, and VJP were observed. In conclusion, CWI elicited generally greater physiological effects compared with PBC while both interventions were more effective than CON in reducing DOMS in females, but had no effect on functional measures or swelling.
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Affiliation(s)
- Erich Hohenauer
- Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Landquart, Switzerland.,International University of Applied Sciences THIM, Landquart, Switzerland.,Department of Movement and Sport Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Joseph T Costello
- School of Sport, Health & Exercise Science, University of Portsmouth, Portsmouth, UK
| | - Tom Deliens
- Department of Movement and Sport Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Peter Clarys
- Department of Movement and Sport Sciences, Vrije Universiteit Brussel, Brussels, Belgium
| | - Rahel Stoop
- Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Landquart, Switzerland.,International University of Applied Sciences THIM, Landquart, Switzerland
| | - Ron Clijsen
- Department of Business Economics, Health and Social Care, University of Applied Sciences and Arts of Southern Switzerland, Landquart, Switzerland.,International University of Applied Sciences THIM, Landquart, Switzerland.,Department of Movement and Sport Sciences, Vrije Universiteit Brussel, Brussels, Belgium
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Ando S, Komiyama T, Sudo M, Higaki Y, Ishida K, Costello JT, Katayama K. The interactive effects of acute exercise and hypoxia on cognitive performance: A narrative review. Scand J Med Sci Sports 2019; 30:384-398. [PMID: 31605635 DOI: 10.1111/sms.13573] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Revised: 09/09/2019] [Accepted: 10/04/2019] [Indexed: 12/13/2022]
Abstract
Acute moderate intensity exercise has been shown to improve cognitive performance. In contrast, hypoxia is believed to impair cognitive performance. The detrimental effects of hypoxia on cognitive performance are primarily dependent on the severity and duration of exposure. In this review, we describe how acute exercise under hypoxia alters cognitive performance, and propose that the combined effects of acute exercise and hypoxia on cognitive performance are mainly determined by interaction among exercise intensity and duration, the severity of hypoxia, and duration of exposure to hypoxia. We discuss the physiological mechanism(s) of the interaction and suggest that alterations in neurotransmitter function, cerebral blood flow, and possibly cerebral metabolism are the primary candidates that determine cognitive performance when acute exercise is combined with hypoxia. Furthermore, acclimatization appears to counteract impaired cognitive performance during prolonged exposure to hypoxia although the precise physiological mechanism(s) responsible for this amelioration remain to be elucidated. This review has implications for sporting, occupational, and recreational activities at terrestrial high altitude where cognitive performance is essential. Further studies are required to understand physiological mechanisms that determine cognitive performance when acute exercise is performed in hypoxia.
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Affiliation(s)
- Soichi Ando
- Graduate School of Informatics and Engineering, The University of Electro-Communications, Tokyo, Japan
| | - Takaaki Komiyama
- Center for Education in Liberal Arts and Sciences, Osaka University, Osaka, Japan
| | - Mizuki Sudo
- Meiji Yasuda Life Foundation of Health and Welfare, Tokyo, Japan
| | - Yasuki Higaki
- Faculty of Sports Science, Fukuoka University, Fukuoka, Japan
| | - Koji Ishida
- Research Center of Health, Physical Fitness and Sports, Nagoya University, Nagoya, Japan
| | - Joseph T Costello
- Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, Portsmouth, UK
| | - Keisho Katayama
- Research Center of Health, Physical Fitness and Sports, Nagoya University, Nagoya, Japan
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Shepherd AI, Costello JT, Bailey SJ, Bishop N, Wadley AJ, Young-Min S, Gilchrist M, Mayes H, White D, Gorczynski P, Saynor ZL, Massey H, Eglin CM. "Beet" the cold: beetroot juice supplementation improves peripheral blood flow, endothelial function, and anti-inflammatory status in individuals with Raynaud's phenomenon. J Appl Physiol (1985) 2019; 127:1478-1490. [PMID: 31343948 DOI: 10.1152/japplphysiol.00292.2019] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Raynaud's phenomenon (RP) is characterized by recurrent transient peripheral vasospasm and lower nitric oxide (NO) bioavailability in the cold. We investigated the effect of nitrate-rich beetroot juice (BJ) supplementation on 1) NO-mediated vasodilation, 2) cutaneous vascular conductance (CVC) and skin temperature (Tsk) following local cooling, and 3) systemic anti-inflammatory status. Following baseline testing, 23 individuals with RP attended four times, in a double-blind, randomized crossover design, following acute and chronic (14 days) BJ and nitrate-depleted beetroot juice (NDBJ) supplementation. Peripheral Tsk and CVC were measured during and after mild hand and foot cooling, and during transdermal delivery of acetylcholine and sodium nitroprusside. Markers of anti-inflammatory status were also measured. Plasma nitrite concentration ([nitrite]) was increased in the BJ conditions (P < 0.001). Compared with the baseline visit, thumb CVC was greater following chronic-BJ (Δ2.0 flux/mmHg, P = 0.02) and chronic-NDBJ (Δ1.45 flux/mmHg, P = 0.01) supplementation; however, no changes in Tsk were observed (P > 0.05). Plasma [interleukin-10] was greater, pan endothelin and systolic and diastolic blood pressure (BP) were reduced, and forearm endothelial function was improved, by both BJ and NDBJ supplementation (P < 0.05). Acute and chronic BJ and NDBJ supplementation improved anti-inflammatory status, endothelial function and blood pressure (BP). CVC following cooling increased post chronic-BJ and chronic-NDBJ supplementation, but no effect on Tsk was observed. The key findings are that beetroot supplementation improves thumb blood flow, improves endothelial function and anti-inflammatory status, and reduces BP in people with Raynaud's.NEW & NOTEWORTHY This is the first study to examine the effect of dietary nitrate supplementation in individuals with Raynaud's phenomenon. The principal novel findings from this study were that both beetroot juice and nitrate-depleted beetroot juice 1) increased blood flow in the thumb following a cold challenge; 2) enhanced endothelium-dependent and -independent vasodilation in the forearm; 3) reduced systolic and diastolic blood pressure, and pan-endothelin concentration; and 4) improved inflammatory status in comparison to baseline.
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Affiliation(s)
- Anthony I Shepherd
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Joseph T Costello
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Stephen J Bailey
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise and Health Sciences, Loughborough University, Epinal Way, Loughborough, United Kingdom
| | - Nicolette Bishop
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise and Health Sciences, Loughborough University, Epinal Way, Loughborough, United Kingdom.,University Hospitals of Leicester NHS Trust, Infirmary Square, Leicester, United Kingdom
| | - Alex J Wadley
- National Centre for Sport and Exercise Medicine, School of Sport, Exercise and Health Sciences, Loughborough University, Epinal Way, Loughborough, United Kingdom.,University Hospitals of Leicester NHS Trust, Infirmary Square, Leicester, United Kingdom
| | - Steven Young-Min
- Rheumatology Department, Portsmouth Hospitals NHS Trust, Portsmouth, United Kingdom
| | - Mark Gilchrist
- University of Exeter Medical School and NIHR Exeter Clinical Research Facility, Royal Devon and Exeter Hospital, Exeter, Devon, United Kingdom
| | - Harry Mayes
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Danny White
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Paul Gorczynski
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Zoe L Saynor
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Heather Massey
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Clare M Eglin
- School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
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Williams TB, Corbett J, McMorris T, Young JS, Dicks M, Ando S, Thelwell RC, Tipton MJ, Costello JT. Cognitive performance is associated with cerebral oxygenation and peripheral oxygen saturation, but not plasma catecholamines, during graded normobaric hypoxia. Exp Physiol 2019; 104:1384-1397. [DOI: 10.1113/ep087647] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 06/11/2019] [Indexed: 11/08/2022]
Affiliation(s)
- Thomas B. Williams
- Extreme Environments LaboratoryDepartment of Sport and Exercise SciencesUniversity of Portsmouth Portsmouth UK
| | - Jo Corbett
- Extreme Environments LaboratoryDepartment of Sport and Exercise SciencesUniversity of Portsmouth Portsmouth UK
| | - Terry McMorris
- Extreme Environments LaboratoryDepartment of Sport and Exercise SciencesUniversity of Portsmouth Portsmouth UK
- Department of Sport and Exercise SciencesUniversity of Chichester Chichester UK
| | - John S. Young
- School of Pharmacy and Biomedical ScienceUniversity of Portsmouth Portsmouth UK
| | - Matt Dicks
- Extreme Environments LaboratoryDepartment of Sport and Exercise SciencesUniversity of Portsmouth Portsmouth UK
| | - Soichi Ando
- Graduate School of Informatics and EngineeringThe University of Electro‐Communications Tokyo Japan
| | - Richard C. Thelwell
- Extreme Environments LaboratoryDepartment of Sport and Exercise SciencesUniversity of Portsmouth Portsmouth UK
| | - Michael J. Tipton
- Extreme Environments LaboratoryDepartment of Sport and Exercise SciencesUniversity of Portsmouth Portsmouth UK
| | - Joseph T. Costello
- Extreme Environments LaboratoryDepartment of Sport and Exercise SciencesUniversity of Portsmouth Portsmouth UK
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Hunt AP, Buller MJ, Maley MJ, Costello JT, Stewart IB. Validity of a noninvasive estimation of deep body temperature when wearing personal protective equipment during exercise and recovery. Mil Med Res 2019; 6:20. [PMID: 31196190 PMCID: PMC6567444 DOI: 10.1186/s40779-019-0208-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 05/24/2019] [Indexed: 01/06/2023] Open
Abstract
BACKGROUND Deep body temperature is a critical indicator of heat strain. However, direct measures are often invasive, costly, and difficult to implement in the field. This study assessed the agreement between deep body temperature estimated from heart rate and that measured directly during repeated work bouts while wearing explosive ordnance disposal (EOD) protective clothing and during recovery. METHODS Eight males completed three work and recovery periods across two separate days. Work consisted of treadmill walking on a 1% incline at 2.5, 4.0, or 5.5 km/h, in a random order, wearing EOD protective clothing. Ambient temperature and relative humidity were maintained at 24 °C and 50% [Wet bulb globe temperature (WBGT) (20.9 ± 1.2) °C] or 32 °C and 60% [WBGT (29.0 ± 0.2) °C] on the separate days, respectively. Heart rate and gastrointestinal temperature (TGI) were monitored continuously, and deep body temperature was also estimated from heart rate (ECTemp). RESULTS The overall systematic bias between TGI and ECTemp was 0.01 °C with 95% limits of agreement (LoA) of ±0.64 °C and a root mean square error of 0.32 °C. The average error statistics among participants showed no significant differences in error between the exercise and recovery periods or the environmental conditions. At TGI levels of (37.0-37.5) °C, (37.5-38.0) °C, (38.0-38.5) °C, and > 38.5 °C, the systematic bias and ± 95% LoA were (0.08 ± 0.58) °C, (- 0.02 ± 0.69) °C, (- 0.07 ± 0.63) °C, and (- 0.32 ± 0.56) °C, respectively. CONCLUSIONS The findings demonstrate acceptable validity of the ECTemp up to 38.5 °C. Conducting work within an ECTemp limit of 38.4 °C, in conditions similar to the present study, would protect the majority of personnel from an excessive elevation in deep body temperature (> 39.0 °C).
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Affiliation(s)
- Andrew P Hunt
- School of Exercise and Nutrition Sciences & Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia.
| | - Mark J Buller
- United States Army Research Institute of Environmental Medicine, Natick, MA, USA
| | - Matthew J Maley
- School of Exercise and Nutrition Sciences & Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia.,Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, Portsmouth, UK
| | - Joseph T Costello
- School of Exercise and Nutrition Sciences & Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia.,Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, Portsmouth, UK
| | - Ian B Stewart
- School of Exercise and Nutrition Sciences & Institute of Health and Biomedical Innovation, Queensland University of Technology, Brisbane, QLD, Australia
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Corbett J, White DK, Barwood MJ, Wagstaff CRD, Tipton MJ, McMorris T, Costello JT. The Effect of Head-to-Head Competition on Behavioural Thermoregulation, Thermophysiological Strain and Performance During Exercise in the Heat. Sports Med 2018; 48:1269-1279. [PMID: 29147922 PMCID: PMC5889783 DOI: 10.1007/s40279-017-0816-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Background It has been suggested that pacing is a thermoregulatory behaviour. We investigated the effect of competition on pacing, performance and thermophysiological strain during exercise in the heat and the psychological factors mediating competition effects. Method Eighteen males (maximum oxygen uptake [VO2max] 3.69 [0.44] L min−1) undertook a preliminary 20-km cool (wet-bulb globe temperature [WBGT] 12 °C) cycling time trial (TT) and three experimental 20-km trials (balanced order): (i) cool TT (CoolSolo); (ii) hot (WBGT 26 °C) TT (HotSolo); (iii) hot head-to-head competition (HotH2H). During TTs, an avatar of the participant’s performance was visible. During HotH2H, participants believed they were competing against another participant, but the competitor’s avatar replicated their own preliminary (cool) TT. Results TTs (min:sec [SD]) slowed with increased ambient temperature [CoolSolo 35:31 (2:11) versus HotSolo 36:10 (2:26); p = 0.011]. This effect was negated by competition; performances were not different between HotH2H [35:17 (1:52)] and CoolSolo (p = 0.160) and were quicker in HotH2H versus HotSolo (p = 0.001). End-exercise rectal temperature, mean body temperature and physiological strain index were (p < 0.05) higher in HotH2H than either solo condition. Despite faster performance and greater thermophysiological strain, rating of perceived exertion (RPE), thermal comfort and sensation, and perceptual strain index were not different between HotH2H and HotSolo. The difference in end-exercise rectal temperature between HotH2H and HotSolo was related to pre-exercise anticipatory heart rate response (r = 0.608, p = 0.010) and participants’ propensity for deliberate risk-taking (B = 0.12, p < 0.001), whereas self-reported resilience predicted change in performance times between HotH2H versus HotSolo (B = − 9.40, p = 0.010). Conclusion Competition changes the relationship between perceived and actual thermophysiological state, altering behavioural thermoregulation and increasing thermophysiological strain; this could increase heat-illness risk. Psychophysiological and psychological measures may identify susceptible individuals.
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Affiliation(s)
- Jo Corbett
- Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, Spinnaker Building, Cambridge Road, Portsmouth, PO1 2ER, UK.
| | - Danny K White
- Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, Spinnaker Building, Cambridge Road, Portsmouth, PO1 2ER, UK
| | - Martin J Barwood
- Department of Sport, Health and Nutrition, Leeds Trinity University, Brownberrie Lane, Horsforth, LS18 5HD, UK
| | - Christopher R D Wagstaff
- Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, Spinnaker Building, Cambridge Road, Portsmouth, PO1 2ER, UK
| | - Michael J Tipton
- Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, Spinnaker Building, Cambridge Road, Portsmouth, PO1 2ER, UK
| | - Terry McMorris
- Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, Spinnaker Building, Cambridge Road, Portsmouth, PO1 2ER, UK.,Institute of Sport, University of Chichester, College Lane, Chichester, PO19 9PE, UK
| | - Joseph T Costello
- Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, Spinnaker Building, Cambridge Road, Portsmouth, PO1 2ER, UK
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37
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Borg DN, Stewart IB, Costello JT, Drovandi CC, Minett GM. The impact of environmental temperature deception on perceived exertion during fixed-intensity exercise in the heat in trained-cyclists. Physiol Behav 2018; 194:333-340. [PMID: 29933029 DOI: 10.1016/j.physbeh.2018.06.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Revised: 06/14/2018] [Accepted: 06/18/2018] [Indexed: 11/29/2022]
Abstract
PURPOSE This study examined the effect of environmental temperature deception on the rating of perceived exertion (RPE) during 30 min of fixed-intensity cycling in the heat. METHODS Eleven trained male cyclists completed an incremental cycling test and four experimental trials. Trials consisted of 30 min cycling at 50% Pmax, once in 24 °C (CON) and three times in 33 °C. In the hot trials, participants were provided with accurate temperature feedback (HOT), or were deceived to believe the temperature was 28 °C (DECLOW) or 38 °C (DECHIGH). During cycling, RPE was recorded every 5 min. Rectal and skin temperature, heart rate and oxygen uptake were continuously measured. Data were analysed using linear mixed model methods in a Bayesian framework, magnitude-based inferences (Cohens d), and the probability that d exceeded the smallest worthwhile change. RESULTS RPE was higher in the heat compared to CON, but not statistically different between the hot conditions (mean [95% credible interval]; DECLOW: 13.0 [11.9, 14.1]; HOT: 13.0 [11.9, 14.1]; DECHIGH: 13.1 [12.0, 14.2]). Heart rate was significantly higher in DECHIGH (141 b·min-1 [132, 149]) compared to all other conditions (DECLOW: 138 b·min-1 [129, 146]; HOT: 138 b·min-1 [129, 145]) after 10 min; however, this did not alter RPE. All other physiological variables did not differ between the hot conditions. CONCLUSION Participants were under the impression they were cycling in different environments; however, this did not influence RPE. These data suggest that for trained cyclists, an awareness of environmental temperature does not contribute to the generation of RPE when exercising at a fixed intensity in the heat.
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Affiliation(s)
- D N Borg
- Institute of Health and Biomedical Innovation and School of Exercise and Nutrition Sciences, Queensland University of Technology, Brisbane, Queensland, Australia.
| | - I B Stewart
- Institute of Health and Biomedical Innovation and School of Exercise and Nutrition Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
| | - J T Costello
- Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - C C Drovandi
- School of Mathematical Sciences and the Australian Research Council Centre of Excellence for Mathematical and Statistical Frontiers, Queensland University of Technology, Brisbane, Queensland, Australia
| | - G M Minett
- Institute of Health and Biomedical Innovation and School of Exercise and Nutrition Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
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Ranchordas MK, Rogerson D, Soltani H, Costello JT. Antioxidants for preventing and reducing muscle soreness after exercise: a Cochrane systematic review. Br J Sports Med 2018; 54:74-78. [PMID: 30054340 DOI: 10.1136/bjsports-2018-099599] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/10/2018] [Indexed: 12/24/2022]
Abstract
OBJECTIVE To determine whether antioxidant supplements and antioxidant-enriched foods can prevent or reduce delayed-onset muscle soreness after exercise. METHODS We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register, the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, SPORTDiscus, trial registers, reference lists of articles and conference proceedings up to February 2017. RESULTS In total, 50 studies were included in this review which included a total of 1089 participants (961 were male and 128 were female) with an age range of 16-55 years. All studies used an antioxidant dosage higher than the recommended daily amount. The majority of trials (47) had design features that carried a high risk of bias due to selective reporting and poorly described allocation concealment, potentially limiting the reliability of their findings. We rescaled to a 0-10 cm scale in order to quantify the actual difference between groups and we found that the 95% CIs for all five follow-up times were all well below the minimal important difference of 1.4 cm: up to 6 hours (MD -0.52, 95% CI -0.95 to -0.08); at 24 hours (MD -0.17, 95% CI -0.42 to 0.07); at 48 hours (mean difference (MD) -0.41, 95% CI -0.69 to -0.12); at 72 hours (MD -0.29, 95% CI -0.59 to 0.02); and at 96 hours (MD -0.03, 95% CI -0.43 to 0.37). Thus, the effect sizes suggesting less muscle soreness with antioxidant supplementation were very unlikely to equate to meaningful or important differences in practice. CONCLUSIONS There is moderate to low-quality evidence that high-dose antioxidant supplementation does not result in a clinically relevant reduction of muscle soreness after exercise of up to 6 hours or at 24, 48, 72 and 96 hours after exercise. There is no evidence available on subjective recovery and only limited evidence on the adverse effects of taking antioxidant supplements.
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Affiliation(s)
- Mayur K Ranchordas
- Academy of Sport and Physical Activity, Sheffield Hallam University, Sheffield, UK
| | - David Rogerson
- Academy of Sport and Physical Activity, Sheffield Hallam University, Sheffield, UK
| | - Hora Soltani
- Centre for Health and Social Care Research, Sheffield Hallam University, Sheffield, UK
| | - Joseph T Costello
- Department of Sport and Exercise Science, University of Portsmouth, Portsmouth, UK
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Abstract
Accurate monitoring of homeostatic perturbations following various psychophysiological stressors is essential in sports and exercise medicine. Various biomarkers are routinely used as monitoring tools in both clinical and elite sport settings. Blood collection and muscle biopsies, both invasive in nature, are considered the gold standard for the analysis of these biomarkers in exercise science. Exploring non-invasive methods of collecting and analysing biomarkers that are capable of providing accurate information regarding exercise-induced physiological and psychological stress is of obvious practical importance. This review describes the potential benefits, and the limitations, of using saliva and urine to ascertain biomarkers capable of identifying important stressors that are routinely encountered before, during, or after intense or unaccustomed exercise, competition, over-training, and inappropriate recovery. In particular, we focus on urinary and saliva biomarkers that have previously been used to monitor muscle damage, inflammation, cardiovascular stress, oxidative stress, hydration status, and brain distress. Evidence is provided from a range of empirical studies suggesting that urine and saliva are both capable of identifying various stressors. Although additional research regarding the efficacy of using urine and/or saliva to indicate the severity of exercise-induced psychophysiological stress is required, it is likely that these non-invasive biomarkers will represent "the future" in sports and exercise medicine.
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Affiliation(s)
- Angus Lindsay
- Program in Physical Therapy and Rehabilitation Sciences, School of Medicine, University of Minnesota, 420 Delaware Street SE, Minneapolis, MN, 55455, USA.
| | - Joseph T Costello
- Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, Spinnaker Building, Cambridge Road, Portsmouth, PO1 2ER, UK
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Costello JT, Rendell RA, Furber M, Massey HC, Tipton MJ, Young JS, Corbett J. Effects of acute or chronic heat exposure, exercise and dehydration on plasma cortisol, IL-6 and CRP levels in trained males. Cytokine 2018; 110:277-283. [PMID: 29402724 DOI: 10.1016/j.cyto.2018.01.018] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 01/09/2018] [Accepted: 01/18/2018] [Indexed: 01/02/2023]
Abstract
This study examined the acute and chronic effects of euhydrated and hypohydrated heat exposure, on biomarkers of stress and inflammation. Eight trained males [mean (SD) age: 21 (3) y; mass: 77.30 (4.88) kg; V̇O2max: 56.9 (7.2) mL kg-1 min-1] undertook two heat acclimation programmes (balanced cross-over design), once drinking to maintain euhydration and once with restricted fluid-intake (permissive dehydration). Days 1, 6, and 11 were 60 min euhydrated exercise-heat stress tests (40 °C; 50% RH, 35% peak power output), days 2-5 and 7-10 were 90 min, isothermal-strain (target rectal temperature: 38.5 °C) exercise-heat sessions. Plasma was obtained pre- and post- exercise on day 1, 2, and 11 and analysed for cortisol, interleukin-6 (IL-6), and C-reactive protein (CRP). Cortisol and CRP were also assessed on day 6. IL-6 was elevated following the initial (acute) 90 min isothermal heat strain exercise-heat exposure (day 2) with permissive dehydration ((pre exercise: 1.0 pg mL-1 [0.9], post-exercise: 1.8 pg mL-1 [1.0], P = .032) and when euhydrated (pre-exercise: 1.0 pg mL-1 [1.4], post-exercise: 1.6 pg mL-1 [2.1], P = .048). Plasma cortisol levels were also elevated but only during permissive dehydration (P = .032). Body mass loss was strongly correlated with Δcortisol (r = -0.688, P = .003). Although there was a trend for post-exercise cortisol to be decreased following both heat acclimation programmes (chronic effects), there were no within or between intervention differences in IL-6 or CRP. In conclusion, acute exercise in the heat increased IL-6 and cortisol only when fluid-intake is restricted. There were no chronic effects of either intervention on biomarkers of inflammation as evidenced by IL-6 and CRP returning to basal level at the end of heat acclimation.
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Affiliation(s)
- Joseph T Costello
- Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, United Kingdom.
| | - Rebecca A Rendell
- Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, United Kingdom; Department of Sport and Physical Activity, Bournemouth University, United Kingdom
| | - Matthew Furber
- University of Hertfordshire, Division of Sport, Health and Exercise Science, College Lane, Hatfield, Hertfordshire AL10 9AB, UK; GlaxoSmithKline (GSK) Human Performance Lab, Unit 2 Brentside Executive Park, Great West Road, Brentford, Middlesex TW8 9DA, UK
| | - Heather C Massey
- Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, United Kingdom
| | - Michael J Tipton
- Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, United Kingdom
| | - John S Young
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, UK
| | - Jo Corbett
- Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, United Kingdom
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Corbett J, Rendell RA, Massey HC, Costello JT, Tipton MJ. Inter-individual variation in the adaptive response to heat acclimation. J Therm Biol 2018; 74:29-36. [DOI: 10.1016/j.jtherbio.2018.03.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 02/28/2018] [Accepted: 03/07/2018] [Indexed: 02/07/2023]
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Costello JT, Allen PB, Levesque R. A Comparison of Ventilation Rates Between a Standard Bag-Valve-Mask and a New Design in a Prehospital Setting During Training Simulations. J Spec Oper Med 2017; 17:59-63. [PMID: 28910470 DOI: 10.55460/6q5d-6cl6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 09/01/2017] [Indexed: 11/09/2022]
Abstract
BACKGROUND Excessive ventilation of sick and injured patients is associated with increased morbidity and mortality. Combat Medical Systems® (CMS) is developing a new bag-valve-mask (BVM) designed to limit ventilation rates. The purpose of this study was to compare ventilation rates between a standard BVM device and the CMS device. METHODS This was a prospective, observational, semirandomized, crossover study using Army Medics. Data were collected during Brigade Combat Team Trauma Training classes at Camp Bullis, Texas. Subjects were observed during manikin simulation training in classroom and field environments, with total duration of manual ventilation and number of breaths given recorded for each device. Analysis was performed on overall ventilation rate in breaths per minute (BPM) and also by grouping the subjects by ventilation rates in low, correct, and high groups based on an ideal rate of 10-12 BPM. RESULTS A total of 89 Medics were enrolled and completed the classroom portion of the study, with a subset of 36 evaluated in the field. A small but statistically significant difference in overall BPM between devices was seen in the classroom (ρ < .001) but not in the field (ρ > .05). The study device significantly decreased the incidence of high ventilation rates when compared by groups in both the classroom (ρ < .001) and the field (ρ = .044), but it also increased the rate of low ventilation rates. CONCLUSION The study device effectively reduced rates of excessive ventilation in the classroom and the field.
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Abstract
BACKGROUND Muscle soreness typically occurs after intense exercise, unaccustomed exercise or actions that involve eccentric contractions where the muscle lengthens while under tension. It peaks between 24 and 72 hours after the initial bout of exercise. Many people take antioxidant supplements or antioxidant-enriched foods before and after exercise in the belief that these will prevent or reduce muscle soreness after exercise. OBJECTIVES To assess the effects (benefits and harms) of antioxidant supplements and antioxidant-enriched foods for preventing and reducing the severity and duration of delayed onset muscle soreness following exercise. SEARCH METHODS We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register, the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, SPORTDiscus, trial registers, reference lists of articles and conference proceedings up to February 2017. SELECTION CRITERIA We included randomised and quasi-randomised controlled trials investigating the effects of all forms of antioxidant supplementation including specific antioxidant supplements (e.g. tablets, powders, concentrates) and antioxidant-enriched foods or diets on preventing or reducing delayed onset muscle soreness (DOMS). We excluded studies where antioxidant supplementation was combined with another supplement. DATA COLLECTION AND ANALYSIS Two review authors independently screened search results, assessed risk of bias and extracted data from included trials using a pre-piloted form. Where appropriate, we pooled results of comparable trials, generally using the random-effects model. The outcomes selected for presentation in the 'Summary of findings' table were muscle soreness, collected at times up to 6 hours, 24, 48, 72 and 96 hours post-exercise, subjective recovery and adverse effects. We assessed the quality of the evidence using GRADE. MAIN RESULTS Fifty randomised, placebo-controlled trials were included, 12 of which used a cross-over design. Of the 1089 participants, 961 (88.2%) were male and 128 (11.8%) were female. The age range for participants was between 16 and 55 years and training status varied from sedentary to moderately trained. The trials were heterogeneous, including the timing (pre-exercise or post-exercise), frequency, dose, duration and type of antioxidant supplementation, and the type of preceding exercise. All studies used an antioxidant dosage higher than the recommended daily amount. The majority of trials (47) had design features that carried a high risk of bias due to selective reporting and poorly described allocation concealment, potentially limiting the reliability of their findings.We tested only one comparison: antioxidant supplements versus control (placebo). No studies compared high-dose versus low-dose, where the low-dose supplementation was within normal or recommended levels for the antioxidant involved.Pooled results for muscle soreness indicated a small difference in favour of antioxidant supplementation after DOMS-inducing exercise at all main follow-ups: up to 6 hours (standardised mean difference (SMD) -0.30, 95% confidence interval (CI) -0.56 to -0.04; 525 participants, 21 studies; low-quality evidence); at 24 hours (SMD -0.13, 95% CI -0.27 to 0.00; 936 participants, 41 studies; moderate-quality evidence); at 48 hours (SMD -0.24, 95% CI -0.42 to -0.07; 1047 participants, 45 studies; low-quality evidence); at 72 hours (SMD -0.19, 95% CI -0.38 to -0.00; 657 participants, 28 studies; moderate-quality evidence), and little difference at 96 hours (SMD -0.05, 95% CI -0.29 to 0.19; 436 participants, 17 studies; low-quality evidence). When we rescaled to a 0 to 10 cm scale in order to quantify the actual difference between groups, we found that the 95% CIs for all five follow-up times were all well below the minimal important difference of 1.4 cm: up to 6 hours (MD -0.52, 95% CI -0.95 to -0.08); at 24 hours (MD -0.17, 95% CI -0.42 to 0.07); at 48 hours (MD -0.41, 95% CI -0.69 to -0.12); at 72 hours (MD -0.29, 95% CI -0.59 to 0.02); and at 96 hours (MD -0.03, 95% CI -0.43 to 0.37). Thus, the effect sizes suggesting less muscle soreness with antioxidant supplementation were very unlikely to equate to meaningful or important differences in practice. Neither of our subgroup analyses to examine for differences in effect according to type of DOMS-inducing exercise (mechanical versus whole body aerobic) or according to funding source confirmed subgroup differences. Sensitivity analyses excluding cross-over trials showed that their inclusion had no important impact on results.None of the 50 included trials measured subjective recovery (return to previous activities without signs or symptoms).There is very little evidence regarding the potential adverse effects of taking antioxidant supplements as this outcome was reported in only nine trials (216 participants). From the studies that did report adverse effects, two of the nine trials found adverse effects. All six participants in the antioxidant group of one trial had diarrhoea and four of these also had mild indigestion; these are well-known side effects of the particular antioxidant used in this trial. One of 26 participants in a second trial had mild gastrointestinal distress. AUTHORS' CONCLUSIONS There is moderate to low-quality evidence that high dose antioxidant supplementation does not result in a clinically relevant reduction of muscle soreness after exercise at up to 6 hours or at 24, 48, 72 and 96 hours after exercise. There is no evidence available on subjective recovery and only limited evidence on the adverse effects of taking antioxidant supplements. The findings of, and messages from, this review provide an opportunity for researchers and other stakeholders to come together and consider what are the priorities, and underlying justifications, for future research in this area.
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Affiliation(s)
- Mayur K Ranchordas
- Sheffield Hallam UniversityDepartment of SportCollegiate Crescent CampusA221 Collegiate Hall, Ecclesall RoadSheffieldSouth YorkshireUKS10 2BP
| | - David Rogerson
- Sheffield Hallam UniversityDepartment of SportCollegiate Crescent CampusA221 Collegiate Hall, Ecclesall RoadSheffieldSouth YorkshireUKS10 2BP
| | - Hora Soltani
- Sheffield Hallam UniversityCentre for Health and Social Care Research32 Collegiate CrescentSheffieldUKS10 2BP
| | - Joseph T Costello
- University of PortsmouthDepartment of Sport and Exercise ScienceSpinnaker BuildingCambridge RoadPortsmouthUKP01 2ER
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Mawhinney C, Low DA, Jones H, Green DJ, Costello JT, Gregson W. Cold Water Mediates Greater Reductions in Limb Blood Flow than Whole Body Cryotherapy. Med Sci Sports Exerc 2017; 49:1252-1260. [PMID: 28141620 DOI: 10.1249/mss.0000000000001223] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE Cold-water immersion (CWI) and whole body cryotherapy (WBC) are widely used recovery methods in an attempt to limit exercise-induced muscle damage, soreness, and functional deficits after strenuous exercise. The aim of this study was to compare the effects of ecologically valid CWI and WBC protocols on postexercise lower limb thermoregulatory, femoral artery, and cutaneous blood flow responses. METHODS Ten males completed a continuous cycle exercise protocol at 70% maximal oxygen uptake until a rectal temperature of 38°C was attained. Participants were then exposed to lower-body CWI (8°C) for 10 min, or WBC (-110°C) for 2 min, in a randomized crossover design. Rectal and thigh skin, deep, and superficial muscle temperatures, thigh, and calf skin blood flow (laser Doppler flowmetry), superficial femoral artery blood flow (duplex ultrasound), and arterial blood pressure were measured before, and for 40 min post, cooling interventions. RESULTS Greater reductions in thigh skin (CWI, -5.9°C ± 1.8°C; WBC, 0.2°C ± 0.5°C; P < 0.001) and superficial (CWI, -4.4°C ± 1.3°C; WBC, -1.8°C ± 1.1°C; P < 0.001) and deep (CWI, -2.9°C ± 0.8°C; WBC, -1.3°C ± 0.6°C; P < 0.001) muscle temperatures occurred immediately after CWI. Decreases in femoral artery conductance were greater after CWI (CWI, -84% ± 11%; WBC, -59% ± 21%, P < 0.02) and thigh (CWI, -80% ± 5%; WBC, -59% ± 14%, P < 0.001), and calf (CWI, -73% ± 13%; WBC, -45% ± 17%, P < 0.001) cutaneous vasoconstriction was greater after CWI. Reductions in rectal temperature were similar between conditions after cooling (CWI, -0.6°C ± 0.4°C; WBC, -0.6°C ± 0.3°C; P = 0.98). CONCLUSION Greater reductions in blood flow and tissue temperature were observed after CWI in comparison with WBC. These novel findings have practical and clinical implications for the use of cooling in the recovery from exercise and injury.
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Affiliation(s)
- Chris Mawhinney
- 1Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, UNITED KINGDOM; 2School of Sport Science, Exercise and Health, The University of Western Australia, Perth, AUSTRALIA; and 3Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, Portsmouth, UNITED KINGDOM
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Maley MJ, Costello JT, Borg DN, Bach AJE, Hunt AP, Stewart IB. An Overt Chemical Protective Garment Reduces Thermal Strain Compared with a Covert Garment in Warm-Wet but Not Hot-Dry Environments. Front Physiol 2017; 8:913. [PMID: 29170644 PMCID: PMC5684487 DOI: 10.3389/fphys.2017.00913] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 10/27/2017] [Indexed: 11/23/2022] Open
Abstract
Objectives: A commercial chemical, biological, radiological and nuclear (CBRN) protective covert garment has recently been developed with the aim of reducing thermal strain. A covert CBRN protective layer can be worn under other clothing, with equipment added for full chemical protection when needed. However, it is unknown whether the covert garment offers any alleviation to thermal strain during work compared with a traditional overt ensemble. Therefore, the aim of this study was to compare thermal strain and work tolerance times during work in an overt and covert ensemble offering the same level of CBRN protection. Methods: Eleven male participants wore an overt (OVERT) or covert (COVERT) CBRN ensemble and walked (4 km·h−1, 1% grade) for a maximum of 120 min in either a wet bulb globe temperature [WBGT] of 21, 30, or 37°C (Neutral, WarmWet and HotDry, respectively). The trials were ceased if the participants' gastrointestinal temperature reached 39°C, heart rate reached 90% of maximum, walking time reached 120 min or due to self-termination. Results: All participants completed 120 min of walking in Neutral. Work tolerance time was greater in OVERT compared with COVERT in WarmWet (P < 0.001, 116.5[9.9] vs. 88.9[12.2] min, respectively), though this order was reversed in HotDry (P = 0.003, 37.3[5.3] vs. 48.4[4.6] min, respectively). The rate of change in mean body temperature and mean skin temperature was greater in COVERT (0.025[0.004] and 0.045[0.010]°C·min−1, respectively) compared with OVERT (0.014[0.004] and 0.027[0.007]°C·min−1, respectively) in WarmWet (P < 0.001 and P = 0.028, respectively). However, the rate of change in mean body temperature and mean skin temperature was greater in OVERT (0.068[0.010] and 0.170[0.026]°C·min−1, respectively) compared with COVERT (0.059[0.004] and 0.120[0.017]°C·min−1, respectively) in HotDry (P = 0.002 and P < 0.001, respectively). Thermal sensation, thermal comfort, and ratings of perceived exertion did not differ between garments at trial cessation (P > 0.05). Conclusion: Those dressed in OVERT experienced lower thermal strain and longer work tolerance times compared with COVERT in a warm-wet environment. However, COVERT may be an optimal choice in a hot-dry environment. These findings have practical implications for those making decisions on the choice of CBRN ensemble to be used during work.
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Affiliation(s)
- Matthew J Maley
- Institute of Health and Biomedical Innovation, School of Exercise and Nutrition Sciences, Queensland University of Technology, Brisbane, QLD, Australia
| | - Joseph T Costello
- Institute of Health and Biomedical Innovation, School of Exercise and Nutrition Sciences, Queensland University of Technology, Brisbane, QLD, Australia.,Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - David N Borg
- Institute of Health and Biomedical Innovation, School of Exercise and Nutrition Sciences, Queensland University of Technology, Brisbane, QLD, Australia
| | - Aaron J E Bach
- Institute of Health and Biomedical Innovation, School of Exercise and Nutrition Sciences, Queensland University of Technology, Brisbane, QLD, Australia
| | - Andrew P Hunt
- Institute of Health and Biomedical Innovation, School of Exercise and Nutrition Sciences, Queensland University of Technology, Brisbane, QLD, Australia
| | - Ian B Stewart
- Institute of Health and Biomedical Innovation, School of Exercise and Nutrition Sciences, Queensland University of Technology, Brisbane, QLD, Australia
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Eglin CM, Costello JT, Bailey SJ, Gilchrist M, Massey H, Shepherd AI. Effects of dietary nitrate supplementation on the response to extremity cooling and endothelial function in individuals with cold sensitivity. A double blind, placebo controlled, crossover, randomised control trial. Nitric Oxide 2017; 70:76-85. [PMID: 28941934 DOI: 10.1016/j.niox.2017.09.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 09/18/2017] [Accepted: 09/18/2017] [Indexed: 01/09/2023]
Abstract
Individuals with cold sensitivity have low peripheral skin blood flow and skin temperature possibly due to reduced nitric oxide (NO•) bioavailability. Beetroot has a high concentration of inorganic nitrate and may increase NO-mediated vasodilation. Using a placebo-controlled, double blind, randomised, crossover design, this study tested the hypotheses that acute beetroot supplementation would increase the rate of cutaneous rewarming following a local cold challenge and augment endothelium-dependent vasodilation in cold sensitive individuals. Thirteen cold sensitive participants completed foot and hand cooling (separately, in 15 °C water for 2 min) with spontaneous rewarming in 30 °C air whilst skin temperature and cutaneous vascular conductance (CVC) were measured (Baseline). On two further separate visits, participants consumed 140 ml of either concentrated beetroot juice (nitrate supplementation) or nitrate-depleted beetroot juice (Placebo) 90 min before resting seated blood pressure was measured. Endothelial function was assessed by measuring CVC at the forearm, finger and foot during iontophoresis of 1% w/v acetylcholine followed by foot and hand cooling as for Baseline. Plasma nitrite concentrations significantly increased in nitrate supplementation compared to Placebo and Baseline (502 ± 246 nmol L-1; 73 ± 45 nmol L-1; 74 ± 49 nmol L-1 respectively; n = 11; P < 0.001). Resting blood pressure and the response to foot and hand cooling did not differ between conditions (all P > 0.05). Nitrate supplementation did not alter endothelial function in the forearm, finger or foot (all P > 0.05) compared to Placebo. Despite a physiologically meaningful rise in plasma nitrite concentrations, acute nitrate supplementation does not alter extremity rewarming, endothelial function or blood pressure in individuals with cold sensitivity.
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Affiliation(s)
- Clare M Eglin
- Department of Sport and Exercise Science, University of Portsmouth, UK
| | - Joseph T Costello
- Department of Sport and Exercise Science, University of Portsmouth, UK
| | - Stephen J Bailey
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Mark Gilchrist
- University of Exeter Medical School, NIHR Exeter Clinical Research Facility, Royal Devon and Exeter Hospital, Exeter, Devon, UK
| | - Heather Massey
- Department of Sport and Exercise Science, University of Portsmouth, UK
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Tipton MJ, Costello JT, Paton JFR. Reply from Michael J. Tipton, Joseph T. Costello and Julian F. R. Paton. J Physiol 2017; 595:6365. [DOI: 10.1113/jp275028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Michael J. Tipton
- Extreme Environments Laboratory, Department of Sport and Exercise Science; University of Portsmouth; Portsmouth UK
| | - Joseph T. Costello
- Extreme Environments Laboratory, Department of Sport and Exercise Science; University of Portsmouth; Portsmouth UK
| | - Julian F. R. Paton
- School of Physiology, Pharmacology and Neuroscience, Biomedical Sciences, University Walk; University of Bristol; Bristol UK
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Moreira DG, Costello JT, Brito CJ, Adamczyk JG, Ammer K, Bach AJ, Costa CM, Eglin C, Fernandes AA, Fernández-Cuevas I, Ferreira JJ, Formenti D, Fournet D, Havenith G, Howell K, Jung A, Kenny GP, Kolosovas-Machuca ES, Maley MJ, Merla A, Pascoe DD, Priego Quesada JI, Schwartz RG, Seixas AR, Selfe J, Vainer BG, Sillero-Quintana M. Thermographic imaging in sports and exercise medicine: A Delphi study and consensus statement on the measurement of human skin temperature. J Therm Biol 2017; 69:155-162. [DOI: 10.1016/j.jtherbio.2017.07.006] [Citation(s) in RCA: 153] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 06/27/2017] [Accepted: 07/17/2017] [Indexed: 11/28/2022]
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Rendell RA, Prout J, Costello JT, Massey HC, Tipton MJ, Young JS, Corbett J. Effects of 10 days of separate heat and hypoxic exposure on heat acclimation and temperate exercise performance. Am J Physiol Regul Integr Comp Physiol 2017; 313:R191-R201. [DOI: 10.1152/ajpregu.00103.2017] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Revised: 05/31/2017] [Accepted: 06/05/2017] [Indexed: 11/22/2022]
Abstract
Adaptations to heat and hypoxia are typically studied in isolation but are often encountered in combination. Whether the adaptive response to multiple stressors affords the same response as when examined in isolation is unclear. We examined 1) the influence of overnight moderate normobaric hypoxia on the time course and magnitude of adaptation to daily heat exposure and 2) whether heat acclimation (HA) was ergogenic and whether this was influenced by an additional hypoxic stimulus. Eight males [V̇o2max = 58.5 (8.3) ml·kg−1·min−1] undertook two 11-day HA programs (balanced-crossover design), once with overnight normobaric hypoxia (HAHyp): 8 (1) h per night for 10 nights [[Formula: see text] = 0.156; SpO2 = 91 (2)%] and once without (HACon). Days 1, 6, and 11 were exercise-heat stress tests [HST (40°C, 50% relative humidity, RH)]; days 2–5 and 7–10 were isothermal strain [target rectal temperature (Tre) ~38.5°C], exercise-heat sessions. A graded exercise test and 30-min cycle trial were undertaken pre-, post-, and 14 days after HA in temperate normoxia (22°C, 55% RH; FIO2 = 0.209). HA was evident on day 6 (e.g., reduced Tre, mean skin temperature (T̄sk), heart rate, and sweat [Na+], P < 0.05) with additional adaptations on day 11 (further reduced T̄sk and heart rate). HA increased plasma volume [+5.9 (7.3)%] and erythropoietin concentration [+1.8 (2.4) mIU/ml]; total hemoglobin mass was unchanged. Peak power output [+12 (20) W], lactate threshold [+15 (18) W] and work done [+12 (20) kJ] increased following HA. The additional hypoxic stressor did not affect these adaptations. In conclusion, a separate moderate overnight normobaric hypoxic stimulus does not affect the time course or magnitude of HA. Performance may be improved in temperate normoxia following HA, but this is unaffected by an additional hypoxic stressor.
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Affiliation(s)
- Rebecca A. Rendell
- Department of Sport and Exercise Science, Faculty of Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Jamie Prout
- School of Physical Education, Sport and Exercise Science, Division of Sciences, University of Otago, Dunedin, New Zealand; and
| | - Joseph T. Costello
- Department of Sport and Exercise Science, Faculty of Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Heather C. Massey
- Department of Sport and Exercise Science, Faculty of Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Michael J. Tipton
- Department of Sport and Exercise Science, Faculty of Science, University of Portsmouth, Portsmouth, United Kingdom
| | - John S. Young
- School of Pharmacy and Biomedical Science, Faculty of Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Jo Corbett
- Department of Sport and Exercise Science, Faculty of Science, University of Portsmouth, Portsmouth, United Kingdom
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50
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Abstract
Many stressors cause an increase in ventilation in humans. This is predominantly reported as an increase in minute ventilation (V̇E). But, the same V̇E can be achieved by a wide variety of changes in the depth (tidal volume, VT ) and number of breaths (respiratory frequency, ƒR ). This review investigates the impact of stressors including: cold, heat, hypoxia, pain and panic on the contributions of ƒR and VT to V̇E to see if they differ with different stressors. Where possible we also consider the potential mechanisms that underpin the responses identified, and propose mechanisms by which differences in ƒR and VT are mediated. Our aim being to consider if there is an overall differential control of ƒR and VT that applies in a wide range of conditions. We consider moderating factors, including exercise, sex, intensity and duration of stimuli. For the stressors reviewed, as the stress becomes extreme V̇E generally becomes increased more by ƒR than VT . We also present some tentative evidence that the pattern of ƒR and VT could provide some useful diagnostic information for a variety of clinical conditions. In The Physiological Society's year of 'Making Sense of Stress', this review has wide-ranging implications that are not limited to one discipline, but are integrative and relevant for physiology, psychophysiology, neuroscience and pathophysiology.
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Affiliation(s)
- Michael J Tipton
- Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, Portsmouth, PO1 2ER, UK
| | - Abbi Harper
- Clinical Fellow in Intensive Care Medicine, Southmead Hospital, Bristol, BS10 5NB, UK
| | - Julian F R Paton
- School of Physiology, Pharmacology and Neuroscience, Biomedical Sciences, University Walk, University of Bristol, Bristol, BS8 1TD, UK
| | - Joseph T Costello
- Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, Portsmouth, PO1 2ER, UK
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