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Grover L, Sklioutovskaya-Lopez K, Parkman JK, Wang K, Hendricks E, Adams-Duffield J, Kim JH. Diet, sex, and genetic predisposition to obesity and type 2 diabetes modulate motor and anxiety-related behaviors in mice, and alter cerebellar gene expression. Behav Brain Res 2023; 445:114376. [PMID: 36868363 PMCID: PMC10065959 DOI: 10.1016/j.bbr.2023.114376] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 12/28/2022] [Accepted: 02/28/2023] [Indexed: 03/05/2023]
Abstract
Obesity and type 2 diabetes (T2D) are serious health problems linked to neurobehavioral alterations. We compared motor function, anxiety-related behavior, and cerebellar gene expression in TALLYHO/Jng (TH), a polygenic model prone to insulin resistance, obesity, and T2D, and normal C57BL/6 J (B6) mice. Male and female mice were weaned onto chow or high fat (HF) diet at 4 weeks of age (wk), and experiments conducted at young (5 wk) and old (14 - 20 wk) ages. In the open field, distance traveled was significantly lower in TH (vs. B6). For old mice, anxiety-like behavior (time in edge zone) was significantly increased for TH (vs B6), females (vs males), and for both ages HF diet (vs chow). In Rota-Rod testing, latency to fall was significantly shorter in TH (vs B6). For young mice, longer latencies to fall were observed for females (vs males) and HF (vs chow). Grip strength in young mice was greater in TH (vs B6), and there was a diet-strain interaction, with TH on HF showing increased strength, whereas B6 on HF showed decreased strength. For older mice, there was a strain-sex interaction, with B6 males (but not TH males) showing increased strength compared to the same strain females. There were significant sex differences in cerebellar mRNA levels, with Tnfα higher, and Glut4 and Irs2 lower in females (vs males). There were significant strain effects for Gfap and Igf1 mRNA levels with lower in TH (vs B6). Altered cerebellar gene expression may contribute to strain differences in coordination and locomotion.
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Affiliation(s)
- Lawrence Grover
- Department of Biomedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV 25755, USA
| | | | - Jacaline K Parkman
- Department of Biomedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV 25755, USA
| | - Katherine Wang
- Department of Biomedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV 25755, USA
| | - Emily Hendricks
- Department of Biomedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV 25755, USA
| | - Jessica Adams-Duffield
- Department of Biomedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV 25755, USA
| | - Jung Han Kim
- Department of Biomedical Sciences, Joan C. Edwards School of Medicine, Marshall University, Huntington, WV 25755, USA.
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La Marra M, Messina A, Ilardi CR, Verde G, Amato R, Esposito N, Troise S, Orlando A, Messina G, Monda V, Di Maio G, Villano I. The Neglected Factor in the Relationship between Executive Functioning and Obesity: The Role of Motor Control. Healthcare (Basel) 2022; 10:1775. [PMID: 36141387 PMCID: PMC9498752 DOI: 10.3390/healthcare10091775] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 09/01/2022] [Accepted: 09/12/2022] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND The association between obesity and executive functions (EFs) is highly controversial. It has been suggested that waist circumference (WC), compared to body mass index (BMI), is a better indicator of fat mass and EFs in obesity. Moreover, according to the viewpoint that the brain's functional architecture meets the need for interactive behavior, we hypothesize that the relationship between EFs and body weight might be mediated by the motor performance. METHODS General executive functioning (frontal assessment battery-15), additional cognitive subdomains (trail making test and digit span backward), and motor performance (finger tapping task) were assessed in a sample that included 330 volunteers (192 females, M age = 45.98 years, SD = 17.70, range = 18-86 years). RESULTS Hierarchical multiple regression analysis indicated that the FAB15 score and FTT negatively predicted WC but not BMI. A subsequent mediation analysis highlighted that the indirect effect of FAB15 on WC through finger tapping was statistically significant. CONCLUSIONS Our results suggest that WC, as compared to BMI, is a more effective measure for studying the association between EFs and body weight. Still, we found that the motor domain partially mediates the dynamics of such a relationship.
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Affiliation(s)
- Marco La Marra
- Department of Experimental Medicine, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy
| | - Antonietta Messina
- Department of Experimental Medicine, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy
| | - Ciro Rosario Ilardi
- Department of Experimental Medicine, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy
- Department of Psychology, University of Campania “Luigi Vanvitelli”, 81100 Caserta, Italy
| | - Giuseppe Verde
- Department of Experimental Medicine, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy
| | - Raffaella Amato
- Neurological Unit, CTO Hospital, AORN “Ospedali dei Colli”, 80131 Naples, Italy
| | - Nadia Esposito
- Department of Experimental Medicine, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy
| | - Simona Troise
- Department of Experimental Medicine, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy
| | - Antonella Orlando
- Department of Experimental Medicine, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy
| | - Giovanni Messina
- Department of Clinical and Experimental Medicine, University of Foggia, 71122 Foggia, Italy
| | - Vincenzo Monda
- Department of Movement Sciences and Wellbeing, University of Naples “Parthenope”, 80133 Naples, Italy
| | - Girolamo Di Maio
- Department of Experimental Medicine, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy
| | - Ines Villano
- Department of Experimental Medicine, University of Campania “Luigi Vanvitelli”, 80138 Naples, Italy
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Baek S, Jung J, Moon P, Park W. Obesity impacts on task performance and perceived discomfort during seated foot target reaches. ERGONOMICS 2021; 64:1569-1578. [PMID: 34018914 DOI: 10.1080/00140139.2021.1933202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 05/14/2021] [Indexed: 06/12/2023]
Abstract
This study examined obesity impacts on task performance and perceived discomfort during seated foot target reaches. Three independent variables, participant group, movement distance, and, movement direction, were considered. The task performance measures employed were reaction time, movement time and task performance time. Perceived discomfort was measured using a modified Borg CR-10 scale. Statistical analyses revealed that: obesity was associated with increases in movement time, reaction time and performance time; movement distance significantly affected the three task performance measures and discomfort rating; and, movement direction significantly affected movement time, performance time and discomfort rating. The obesity impacts observed are thought to reflect the decelerating effects of the extra fat mass in the obese body during foot reaches and possibly obesity-related physiological and cognitive changes. Design improvements of foot-operated systems, such as reducing distances to targets, increasing target sizes and avoiding forward foot reaches, may help counteract the observed obesity impacts. Practitioner Summary: This study empirically investigated the obesity impacts on task performance and perceived discomfort during seated foot target reaches. Obesity was found to be associated with increases in movement time, reaction time and performance time. The observed obesity impacts seem attributable to the anthropometric, motor and cognitive characteristics of the obese.Abbreviations: ANOVA: analysis of variance; BMI: body mass index; ROM: range of motion; Borg CR-10: Borg's category ratio 10 scale.
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Affiliation(s)
- Seungwon Baek
- Department of Industrial Engineering, Seoul National University, Seoul, South Korea
| | - Jaemoon Jung
- Department of Industrial Engineering, Seoul National University, Seoul, South Korea
| | - Philjun Moon
- Department of Industrial Engineering, Seoul National University, Seoul, South Korea
| | - Woojin Park
- Department of Industrial Engineering, Seoul National University, Seoul, South Korea
- Institute for Industrial Systems Innovation, Seoul National University, Seoul, South Korea
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Mehta RK, Rhee J. Revealing Sex Differences During Upper and Lower Extremity Neuromuscular Fatigue in Older Adults Through a Neuroergonomics Approach. FRONTIERS IN NEUROERGONOMICS 2021; 2:663368. [PMID: 38235250 PMCID: PMC10790897 DOI: 10.3389/fnrgo.2021.663368] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 07/26/2021] [Indexed: 01/19/2024]
Abstract
Background: Sex differences in neuromuscular fatigue is well-documented, however the underlying mechanisms remain understudied, particularly for the aging population. Objective: This study investigated sex differences in fatigability of the upper and lower extremity of older adults using a neuroergonomics approach. Methods: Thirty community-dwelling older adults (65 years or older; 15 M, 15 F) performed intermittent submaximal fatiguing handgrip and knee extension exercises until voluntary exhaustion on separate days. Muscle activity from prime muscles of the hand/arm and knee extensors were monitored using electromyography, neural activity from the frontal, motor, and sensory areas were monitored using functional near infrared spectroscopy, and force output were obtained. Results: While older males were stronger than females across both muscle groups, they exhibited longer endurance times and greater strength loss during knee extension exercises. These lower extremity findings were associated with greater force complexity over time and concomitant increase in left motor and right sensory motor regions. While fatigability during handgrip exercises was comparable across sexes, older females exhibited concurrent increases in the activation of the ipsilateral motor regions over time. Discussion: We identified differences in the underlying central neural strategies adopted by males and females in maintaining downstream motor outputs during handgrip fatigue that were not evident with traditional ergonomics measures. Additionally, enhanced neural activation in males during knee exercises that accompanied longer time to exhaustion point to potential rehabilitation/exercise strategies to improve neuromotor outcomes in more fatigable older adults.
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Affiliation(s)
- Ranjana K. Mehta
- Wm. Michael Barnes '64 Department of Industrial & Systems Engineering, Texas A&M University, College Station, TX, United States
| | - Joohyun Rhee
- Department of Environmental and Occupational Health, Texas A&M University, College Station, TX, United States
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Tyagi O, Zhu Y, Johnson C, Mehta RK, Sasangohar F, Erraguntla M, Qaraqe K. Neural Signatures of Handgrip Fatigue in Type 1 Diabetic Men and Women. Front Hum Neurosci 2020; 14:564969. [PMID: 33240061 PMCID: PMC7680760 DOI: 10.3389/fnhum.2020.564969] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2020] [Accepted: 10/14/2020] [Indexed: 01/22/2023] Open
Abstract
Type 1 diabetes (T1D) is associated with reduced muscular strength and greater muscle fatigability. Along with changes in muscular mechanisms, T1D is also linked to structural changes in the brain. How the neurophysiological mechanisms underlying muscle fatigue is altered with T1D and sex related differences of these mechanisms are still not well investigated. The aim of this study was to determine the impact of T1D on the neural correlates of handgrip fatigue and examine sex and T1D related differences in neuromuscular performance parameters, neural activation and functional connectivity patterns between the motor regions of the brain. Forty-two adults, balanced by condition (healthy vs T1D) and sex (male vs female), and performed submaximal isometric handgrip contractions until voluntary exhaustion. Initial strength, endurance time, strength loss, force variability, and complexity measures were collected. Additionally, hemodynamic responses from motor-function related cortical regions, using functional near-infrared spectroscopy (fNIRS), were obtained. Overall, females exhibited lower initial strength (p < 0.0001), and greater strength loss (p = 0.023) than males. While initial strength was significantly lower in the T1D group (p = 0.012) compared to the healthy group, endurance times and strength loss were comparable between the two groups. Force complexity, measured as approximate entropy, was found to be lower throughout the experiment for the T1D group (p = 0.0378), indicating lower online motor adaptability. Although, T1D and healthy groups fatigued similarly, only the T1D group exhibited increased neural activation in the left (p = 0.095) and right (p = 0.072) supplementary motor areas (SMA) over time. A sex × condition × fatigue interaction effect (p = 0.044) showed that while increased activation was observed in both T1D females and healthy males from the Early to Middle phase, this was not observed in healthy females or T1D males. These findings demonstrate that T1D adults had lower adaptability to fatigue which they compensated for by increasing neural effort. This study highlights the importance of examining both neural and motor performance signatures when investigating the impact of chronic conditions on neuromuscular fatigue. Additionally, the findings have implications for developing intervention strategies for training, rehabilitation, and ergonomics considerations for individuals with chronic conditions.
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Affiliation(s)
- Oshin Tyagi
- Department of Industrial and Systems Engineering, Texas A&M University, College Station, TX, United States
| | - Yibo Zhu
- Department of Industrial and Systems Engineering, Texas A&M University, College Station, TX, United States
| | - Connor Johnson
- Department of Industrial and Systems Engineering, Texas A&M University, College Station, TX, United States
| | - Ranjana K. Mehta
- Department of Industrial and Systems Engineering, Texas A&M University, College Station, TX, United States
| | - Farzan Sasangohar
- Department of Industrial and Systems Engineering, Texas A&M University, College Station, TX, United States
| | - Madhav Erraguntla
- Department of Industrial and Systems Engineering, Texas A&M University, College Station, TX, United States
| | - Khalid Qaraqe
- Department of Electrical and Computer Engineering, Texas A&M University at Qatar, Doha, Qatar
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Urquhart EL, Wang X, Liu H, Fadel PJ, Alexandrakis G. Differences in Net Information Flow and Dynamic Connectivity Metrics Between Physically Active and Inactive Subjects Measured by Functional Near-Infrared Spectroscopy (fNIRS) During a Fatiguing Handgrip Task. Front Neurosci 2020; 14:167. [PMID: 32210748 PMCID: PMC7076120 DOI: 10.3389/fnins.2020.00167] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 02/14/2020] [Indexed: 12/11/2022] Open
Abstract
Twenty-three young adults (4 Females, 25.13 ± 3.72 years) performed an intermittent maximal handgrip force task using their dominant hand for 20 min (3.5 s squeeze/6.5 s release, 120 blocks) with concurrent cortical activity imaging by functional Near-Infrared Spectroscopy (fNRIS; OMM-3000, Shimadzu Corp., 111 channels). Subjects were grouped as physically active (n = 10) or inactive (n = 12) based on a questionnaire (active-exercise at least four times a week, inactive- exercise less than two times a week). We explored how motor task fatigue affected the vasomotion-induced oscillations in ΔHbO as measured by fNIRS at each hemodynamic frequency band: endothelial component (0.003–0.02 Hz) associated to microvascular activity, neurogenic component (0.02–0.04 Hz) related to intrinsic neuronal activity, and myogenic component (0.04–0.15 Hz) linked to activity of smooth muscles of arterioles. To help understand how these three neurovascular regulatory mechanisms relate to handgrip task performance we quantified several dynamic fNIRS metrics, including directional phase transfer entropy (dPTE), a computationally efficient and data-driven method used as a marker of information flow between cortical regions, and directional connectivity (DC), a means to compute directionality of information flow between two cortical regions. The relationship between static functional connectivity (SFC) and functional connectivity variability (FCV) was also explored to understand their mutual dependence for each frequency band in the context of handgrip performance as fatigued increased. Our findings ultimately showed differences between subject groups across all fNIRS metrics and hemodynamic frequency bands. These findings imply that physical activity modulates neurovascular control mechanisms at the endogenic, neurogenic, and myogenic frequency bands resulting in delayed fatigue onset and enhanced performance. The dynamic cortical network metrics quantified in this work for young, healthy subjects provides baseline measurements to guide future work on older individuals and persons with impaired cardiovascular health.
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Affiliation(s)
- Elizabeth L Urquhart
- Bioengineering Department, University of Texas at Arlington, Arlington, TX, United States
| | - Xinlong Wang
- Bioengineering Department, University of Texas at Arlington, Arlington, TX, United States
| | - Hanli Liu
- Bioengineering Department, University of Texas at Arlington, Arlington, TX, United States
| | - Paul J Fadel
- Department of Kinesiology, University of Texas at Arlington, Arlington, TX, United States
| | - George Alexandrakis
- Bioengineering Department, University of Texas at Arlington, Arlington, TX, United States
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Urquhart EL, Wanniarachchi HI, Wang X, Liu H, Fadel PJ, Alexandrakis G. Mapping cortical network effects of fatigue during a handgrip task by functional near-infrared spectroscopy in physically active and inactive subjects. NEUROPHOTONICS 2019; 6:045011. [PMID: 31853458 PMCID: PMC6904890 DOI: 10.1117/1.nph.6.4.045011] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Accepted: 11/19/2019] [Indexed: 05/29/2023]
Abstract
The temporal evolution of cortical activation and connectivity patterns during a fatiguing handgrip task were studied by functional near-infrared spectroscopy (fNIRS). Twenty-three young adults (18 to 35 years old) were recruited to use a handheld force sensor to perform intermittent handgrip contractions with their dominant hand at their personal maximum voluntary contraction force level for 3.5 s followed by 6.5 s of rest for 120 blocks. Subjects were divided into self-reported physically active and inactive groups, and their hemodynamic activity over the prefrontal and sensory-motor cortices (111 channels) was mapped while they performed this task. Using this fNIRS setup, a more detailed time sequence of cortical activation and connectivity patterns was observed compared to prior studies. A temporal evolution sequence of hemodynamic activation patterns was noted, which was different between the active and the inactive groups. Physically active subjects demonstrated delayed fatigue onset and significantly longer-lasting and more spatially extended functional connectivity (FC) patterns, compared to inactive subjects. The observed differences in activation and FC suggested differences in cortical network adaptation patterns as fatigue set in, which were dependent on subjects' physical activity. The findings of this study suggest that physical activity increases FC with regions involved in motor task control and correlates to extended fatigue onset and enhanced performance.
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Affiliation(s)
- Elizabeth L. Urquhart
- University of Texas at Arlington, Bioengineering Department, Arlington, Texas, United States
| | | | - Xinlong Wang
- University of Texas at Arlington, Bioengineering Department, Arlington, Texas, United States
| | - Hanli Liu
- University of Texas at Arlington, Bioengineering Department, Arlington, Texas, United States
| | - Paul J. Fadel
- University of Texas at Arlington, Department of Kinesiology, Arlington, Texas, United States
| | - George Alexandrakis
- University of Texas at Arlington, Bioengineering Department, Arlington, Texas, United States
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Mendez-Rebolledo G, Guzman-Muñoz E, Ramírez-Campillo R, Valdés-Badilla P, Cruz-Montecinos C, Morales-Verdugo J, Berral de la Rosa FJ. Influence of adiposity and fatigue on the scapular muscle recruitment order. PeerJ 2019; 7:e7175. [PMID: 31275760 PMCID: PMC6598653 DOI: 10.7717/peerj.7175] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Accepted: 05/23/2019] [Indexed: 01/27/2023] Open
Abstract
Background Several authors have indicated that excess body weight can modify the electromyographic (EMG) amplitude due to the accumulation of subcutaneous fat. This accumulation of adipose tissue around the muscle would affect the metabolic capacity during functional activities. On the other hand, some authors have not observed differences in the myoelectric manifestations of fatigue between normal weight and obese people. Furthermore, these manifestations have not been investigated regarding EMG onset latency, which indicates a pattern of muscle activation between different muscles. The objective of this study was to determine whether an increase in body weight, skinfolds, and muscle fatigue modify the trapezius and serratus anterior (SA) onset latencies and to determine the scapular muscle recruitment order in fatigue and excess body weight conditions. Methods This cross-sectional study was carried out in a university laboratory. The participants were randomly assigned to the no-fatigue group (17 participants) or the fatigue (17 participants) group. The body mass index, skinfold thickness (axillary, pectoral, and subscapular), and percentage of body fat were measured. In addition, the onset latency of the scapular muscles [lower trapezius (LT), middle trapezius (MT), upper trapezius (UT), and SA] was assessed by surface EMG during the performance of a voluntary arm raise task. A multiple linear regression model was adjusted and analyzed for the additive combination of the variables, percentage body fat, skinfold thickness, and fatigue. The differences in onset latency between the scapular muscles were analyzed using a three-way repeated measure analysis of variance. In all the tests, an alpha level <0.05 was considered statistically significant. Results For the MT, LT, and SA onset latencies, the body mass index was associated with a delayed onset latency when it was adjusted for the additive combination of percentage of body fat, skinfold thickness, and fatigue. Of these adjustment factors, the subscapular skinfold thickness (R 2 = 0.51; β = 10.7; p = 0.001) and fatigue (R 2 = 0.86; β = 95.4; p = 0.001) primarily contributed to the increase in SA onset latency. A significant muscle ×body mass index ×fatigue interaction (F = 4.182; p = 0.008) was observed. In the fatigue/excess body weight condition, the UT was activated significantly earlier than the other three scapular muscles (p < 0.001) and SA activation was significantly delayed compared to LT (p < 0.001). Discussion Excess body weight, adjusted for skinfold thickness (axillary and subscapular) and fatigue, increases the onset latency of the MT, LT, and SA muscles and modifies the recruitment order of scapular muscles. In fact, the scapular stabilizing muscles (MT, LT, and SA) increase their onset latency in comparison to the UT muscle. These results were not observed when excess body weight was considered as an individual variable or when adjusted by the percentage body fat.
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Affiliation(s)
- Guillermo Mendez-Rebolledo
- Escuela de Kinesiología, Facultad de Salud, Universidad Santo Tomás, Chile.,Universidad Pablo de Olavide, Seville, Spain
| | | | - Rodrigo Ramírez-Campillo
- Laboratory of Human Performance, Quality of Life and Wellness Research Group, Department of Physical Activity Sciences, Universidad de Los Lagos, Osorno, Chile
| | - Pablo Valdés-Badilla
- Institute of Physical Activity and Health, Universidad Autónoma de Chile, Temuco, Chile
| | - Carlos Cruz-Montecinos
- Department of Physical Therapy, Laboratory of Clinical Biomechanics, Faculty of Medicine, University of Chile, Santiago, Chile
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Impacts of the late adulthood diet-induced obesity onset on behavior, immune function, redox state and life span of male and female mice. Brain Behav Immun 2019; 78:65-77. [PMID: 30659939 DOI: 10.1016/j.bbi.2019.01.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Revised: 01/14/2019] [Accepted: 01/14/2019] [Indexed: 11/21/2022] Open
Abstract
The aim of the present study was to investigate whether the late onset of diet-induced obesity (DIO) in middle-aged mice affected behavioral, immunological and oxidative stress parameters as well as life span of male and female mice. Also, it was analyzed whether the late DIO onset aggravated immunosenescence in old female mice. Late-adult male and female ICR/CD1 mice (28 weeks old) were fed either a high-fat diet or a standard diet during 14 weeks. After that, in these middle-aged (42 weeks old) diet-induced obese (DIO) and non-DIO controls, behavior as well as functions and redox state of peritoneal leukocytes were evaluated. These same parameters (excepting behavioral tests) were repeated when female mice were old (72 weeks old). The results showed lower exploratory activity and higher anxiety-like behavior in middle-aged male and female DIO than in controls. Moreover, these DIO animals from both sexes exhibited statistically significant impaired immune cell functions, such as chemotaxis of macrophages and lymphocytes, phagocytosis of macrophages, natural killer activity and lymphoproliferation in response to ConA and LPS, as well as an oxidative stress state in comparison with controls. Male DIO mice exhibited higher impairments in a variety of the evaluated parameters and a shorter life span than their female counterparts. In addition, female DIO mice, at old age, showed aggravated immunosenescence. In conclusion, the late DIO onset leads to impairments in behavior as well as in immune system functions of middle-aged male and female mice, males being significantly more affected than females.
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Rhee J, Mehta RK. Functional Connectivity During Handgrip Motor Fatigue in Older Adults Is Obesity and Sex-Specific. Front Hum Neurosci 2018; 12:455. [PMID: 30483085 PMCID: PMC6243051 DOI: 10.3389/fnhum.2018.00455] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Accepted: 10/25/2018] [Indexed: 12/12/2022] Open
Abstract
The prevalence of obesity in older adults, particularly in females, is increasing rapidly and is associated with declines in both the brain and physical health. Both the obese and the female populations have shown greater motor fatigue than their counterparts, however, the central neural mechanisms for fatigue are unclear. The present study measured fatigue-related functional connectivity across frontal and sensorimotor areas using functional near-infrared spectroscopy (fNIRS). Fifty-nine older adults (30 non-obese and 29 obese) performed submaximal handgrip motor fatigue until voluntary exhaustion. Functional connectivity and cerebral hemodynamics were compared across eight cortical areas during motor fatigue and across obesity and sex groups along with neuromuscular fatigue outcomes (i.e., endurance time, strength loss, and force steadiness). Both obesity- and sex-specific functional architecture and mean activation differences during motor fatigue in older adults were observed, which were accompanied by fatigue-related changes in variability of force steadiness that differed between groups. While primary indicators of fatigue, i.e., endurance and strength loss, did not differ between groups, the motor steadiness changes indicated different neural adaptation strategies between the groups. These findings indicate that obesity and sex differences exist in brain function in older adults, which may affect performance during motor fatigue.
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Affiliation(s)
- Joohyun Rhee
- Department of Occupational and Environmental Health, School of Public Health, Texas A&M University, College Station, TX, United States
| | - Ranjana K Mehta
- Department of Occupational and Environmental Health, School of Public Health, Texas A&M University, College Station, TX, United States.,Department of Industrial and Systems Engineering, Texas A&M University, College Station, TX, United States
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11
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Abstract
OBJECTIVE The objective of the current study was to determine the effect of body mass index (BMI) on fatigability of three different muscle groups at four different work intensities. METHODS Forty-nine normal-weight, 50 overweight, and 43 obese adults (32.1 ± 9.2 years; 50% males) performed fatiguing handgrip, shoulder flexion, and trunk extension exertions at 20%, 40%, 60%, and 80% of the associated maximum voluntary contractions. RESULTS Obese adults demonstrated 22% to 30% shorter endurance times than normal-weight adults, but this was only observed at lower intensities and with larger and more postural muscles of the shoulder and low back. Strength and fatigue-related strength loss remained comparable across BMI groups in both males and females in these task-specific conditions. Obesity was associated with faster progression in perception of effort at low-intensity shoulder and trunk exertions. While males were stronger than females across all muscle groups, females exhibited greater shoulder fatigue resistance than males at lower intensity levels. CONCLUSION Findings indicate that the relationship between obesity and fatigability is task dependent. APPLICATION These findings provide initial evidence on the impact of obesity on worker capacity. Future work that extends the current investigation to include more occupationally relevant scenarios are needed to facilitate occupational task (re)design and assessment practices, such that altered work capacities of two-thirds of the working population are accommodated.
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12
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Pajoutan M, Ghesmaty Sangachin M, Cavuoto LA. Central and peripheral fatigue development in the shoulder muscle with obesity during an isometric endurance task. BMC Musculoskelet Disord 2017; 18:314. [PMID: 28732481 PMCID: PMC5521062 DOI: 10.1186/s12891-017-1676-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 07/13/2017] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Fatigue increases the likelihood of developing work-related musculoskeletal disorders and injury. Due to the physiological and neuromuscular changes that accompany obesity, it may alter the fatigue development mechanism and exacerbate injury risk. The upper extremities have the highest incidence rates for work-related musculoskeletal disorders. Therefore, the goals of this study were to investigate the effect of obesity on central vs. peripheral fatigue as well as on the physical signs of fatigue on the middle deltoid muscle. METHODS A measure of central activation ratio was used to quantify central fatigue by considering the increment in the torque output by superimposed twitch relative to its corresponding maximum voluntary contraction. For this purpose, electrical stimulation was delivered at the middle deltoid muscles of 22 non-obese (18 < body mass index (BMI) < 25 kg/m2) and 17 obese (30 < BMI < 40 kg/m2) individuals aged 18-32 years old. Participants completed superimposed maximum voluntary isometric contractions of shoulder abduction before and after a sustained isometric fatiguing task at either 30 or 60% of the muscle capacity. Differences in endurance time, torque fluctuation, torque loss, and muscle activity measured by an electromyography sensor were also investigated. RESULTS A greater reduction of voluntary activation of motor units (p = 0.001) with fatigue was observed for individuals who are obese. Contrary to the effect of obesity on central fatigue, a trend toward reduced peripheral fatigue (p = 0.06) was observed for the obese group compared to the non-obese group. On average, a 14% higher rate of torque loss per second was observed among individuals with obesity in comparison to non-obese participants. CONCLUSIONS The observed greater contribution of central fatigue during the sustained endurance tasks suggests that among young healthy obese individuals, the faster fatigue development with obesity, commonly reported in the literature, is most likely due to the central elements rather than the peripheral factors. This finding has implications for fatigue prevention programs during sustained exertions and can help to develop training, work, and rest schedules considering obesity.
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Affiliation(s)
- Mojdeh Pajoutan
- Industrial and Systems Engineering, University at Buffalo, 324 Bell Hall Buffalo, New York, 14260, USA
| | | | - Lora A Cavuoto
- Industrial and Systems Engineering, University at Buffalo, 324 Bell Hall Buffalo, New York, 14260, USA.
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13
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Age-specific neural strategies to maintain motor performance after an acute social stress bout. Exp Brain Res 2017; 235:2049-2057. [PMID: 28357463 DOI: 10.1007/s00221-017-4949-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 03/24/2017] [Indexed: 12/17/2022]
Abstract
Stress due to cognitive demands and fatigue have shown to impair motor performance in older adults; however, the effect of social stress and its influence on prefrontal cortex (PFC) functioning in older adults during upper extremity motor performance tasks is not known. The present study explored the after-effects of an acute social stress bout on neural strategies, measured using PFC and hand/arm muscle activation, and adopted by younger and older adults to maintain handgrip force control. Nine older [74.1 (6.5) years; three men, six women] and ten younger [24.2 (5.0) years, four men, six women] adults performed handgrip force control trials at 30% maximum voluntary contractions before and after the Trier Social Stress Test (TSST). PFC activity was measured using functional near infrared spectroscopy and muscle activity from the flexor and extensor carpi radialis (FCR/ECR) was measured using electromyography. In general, aging was associated with decreased force steadiness and force complexity with a concomitant increase in bilateral PFC activity. While motor performance remained comparable before and after the TSST stress session in both age groups, the associated neural strategies differed between groups. While the stress condition was associated with lower FCR and ECR activity in younger adults despite no change in the PFC activation, stress was associated with increases in FCR activity in older adults. This stress-related compensatory neural strategy of increasing hand/arm muscle activation, potentially via the additional recruitment of the stress-motor neural circuitry, may have played a role in maintaining motor performance in older adults.
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14
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Shortz AE, Mehta RK. Cognitive challenges, aging, and neuromuscular fatigue. Physiol Behav 2017; 170:19-26. [DOI: 10.1016/j.physbeh.2016.11.034] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 11/10/2016] [Accepted: 11/24/2016] [Indexed: 11/29/2022]
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McKendrick R, Mehta R, Ayaz H, Scheldrup M, Parasuraman R. Prefrontal Hemodynamics of Physical Activity and Environmental Complexity During Cognitive Work. HUMAN FACTORS 2017; 59:147-162. [PMID: 28146680 DOI: 10.1177/0018720816675053] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
OBJECTIVE The aim of this study was to assess performance and cognitive states during cognitive work in the presence of physical work and in natural settings. BACKGROUND Authors of previous studies have examined the interaction between cognitive and physical work, finding performance decrements in working memory. Neuroimaging has revealed increases and decreases in prefrontal oxygenated hemoglobin during the interaction of cognitive and physical work. The effect of environment on cognitive-physical dual tasking has not been previously considered. METHOD Thirteen participants were monitored with wireless functional near-infrared spectroscopy (fNIRS) as they performed an auditory 1-back task while sitting, walking indoors, and walking outdoors. RESULTS Relative to sitting and walking indoors, auditory working memory performance declined when participants were walking outdoors. Sitting during the auditory 1-back task increased oxygenated hemoglobin and decreased deoxygenated hemoglobin in bilateral prefrontal cortex. Walking reduced the total hemoglobin available to bilateral prefrontal cortex. An increase in environmental complexity reduced oxygenated hemoglobin and increased deoxygenated hemoglobin in bilateral prefrontal cortex. CONCLUSION Wireless fNIRS is capable of monitoring cognitive states in naturalistic environments. Selective attention and physical work compete with executive processing. During executive processing loading of selective attention and physical work results in deactivation of bilateral prefrontal cortex and degraded working memory performance, indicating that physical work and concomitant selective attention may supersede executive processing in the distribution of mental resources. APPLICATION This research informs decision-making procedures in work where working memory, physical activity, and attention interact. Where working memory is paramount, precautions should be taken to eliminate competition from physical work and selective attention.
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Affiliation(s)
- Ryan McKendrick
- Northrop Grumman Aerospace Systems, Redondo Beach, California
- George Mason University, Fairfax, Virginia
| | - Ranjana Mehta
- Texas A&M University, College Station
- George Mason University, Fairfax, Virginia
| | - Hasan Ayaz
- Drexel University, Philadelphia, Pennsylvania
- George Mason University, Fairfax, Virginia
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Osofundiya O, Benden ME, Dowdy D, Mehta RK. Obesity-specific neural cost of maintaining gait performance under complex conditions in community-dwelling older adults. Clin Biomech (Bristol, Avon) 2016; 35:42-8. [PMID: 27124085 DOI: 10.1016/j.clinbiomech.2016.03.011] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2015] [Revised: 02/23/2016] [Accepted: 03/31/2016] [Indexed: 02/07/2023]
Abstract
BACKGROUND Recent evidence of obesity-related changes in the prefrontal cortex during cognitive and seated motor activities has surfaced; however, the impact of obesity on neural activity during ambulation remains unclear. The purpose of this study was to determine obesity-specific neural cost of simple and complex ambulation in older adults. METHODS Twenty non-obese and obese individuals, 65years and older, performed three tasks varying in the types of complexity of ambulation (simple walking, walking+cognitive dual-task, and precision walking). Maximum oxygenated hemoglobin, a measure of neural activity, was measured bilaterally using a portable functional near infrared spectroscopy system, and gait speed and performance on the complex tasks were also obtained. FINDINGS Complex ambulatory tasks were associated with ~2-3.5 times greater cerebral oxygenation levels and ~30-40% slower gait speeds when compared to the simple walking task. Additionally, obesity was associated with three times greater oxygenation levels, particularly during the precision gait task, despite obese adults demonstrating similar gait speeds and performances on the complex gait tasks as non-obese adults. INTERPRETATION Compared to existing studies that focus solely on biomechanical outcomes, the present study is one of the first to examine obesity-related differences in neural activity during ambulation in older adults. In order to maintain gait performance, obesity was associated with higher neural costs, and this was augmented during ambulatory tasks requiring greater precision control. These preliminary findings have clinical implications in identifying individuals who are at greater risk of mobility limitations, particularly when performing complex ambulatory tasks.
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Affiliation(s)
- Olufunmilola Osofundiya
- Department of Environmental and Occupational Health, Texas A&M University, 1266 TAMU, College Station, TX 77843, USA
| | - Mark E Benden
- Department of Environmental and Occupational Health, Texas A&M University, 1266 TAMU, College Station, TX 77843, USA
| | - Diane Dowdy
- Department of Health Promotion and Community Health Sciences, Texas A&M University, 1266 TAMU, College Station, TX 77843, USA
| | - Ranjana K Mehta
- Department of Environmental and Occupational Health, Texas A&M University, 1266 TAMU, College Station, TX 77843, USA.
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17
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Obesity Reduces Cognitive and Motor Functions across the Lifespan. Neural Plast 2016; 2016:2473081. [PMID: 26881095 PMCID: PMC4737453 DOI: 10.1155/2016/2473081] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Accepted: 10/15/2015] [Indexed: 12/11/2022] Open
Abstract
Due to a sedentary lifestyle, more and more people are becoming obese nowadays. In addition to health-related problems, obesity can also impair cognition and motor performance. Previous results have shown that obesity mainly affects cognition and motor behaviors through altering brain functions and musculoskeletal system, respectively. Many factors, such as insulin/leptin dysregulation and inflammation, mediate the effect of obesity and cognition and motor behaviors. Substantial evidence has suggested exercise to be an effective way to improve obesity and related cognitive and motor dysfunctions. This paper aims to discuss the association of obesity with cognition and motor behaviors and its underlying mechanisms. Following this, mechanisms of exercise to improve obesity-related dysfunctions are described. Finally, implications and future research direction are raised.
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Shortz AE, Pickens A, Zheng Q, Mehta RK. The effect of cognitive fatigue on prefrontal cortex correlates of neuromuscular fatigue in older women. J Neuroeng Rehabil 2015; 12:115. [PMID: 26689713 PMCID: PMC4687384 DOI: 10.1186/s12984-015-0108-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 12/15/2015] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND As the population of adults aged 65 and above is rapidly growing, it is crucial to identify physical and cognitive limitations pertaining to daily living. Cognitive fatigue has shown to adversely impact neuromuscular function in younger adults, however its impact on neuromuscular fatigue, and associated brain function changes, in older adults is not well understood. The aim of the study was to examine the impact of cognitive fatigue on neuromuscular fatigue and associated prefrontal cortex (PFC) activation patterns in older women. METHODS Eleven older (75.82 (7.4) years) females attended two sessions and performed intermittent handgrip exercises at 30 % maximum voluntary contraction (MVC) until voluntary exhaustion after a 60-min control (watching documentary) and 60-min cognitive fatigue (performing Stroop Color Word and 1-Back tests) condition. Dependent measures included endurance time, strength loss, PFC activity (measured using fNIRS), force fluctuations, muscle activity, cardiovascular responses, and perceived discomfort. RESULTS Participants perceived greater cognitive fatigue after the 60-min cognitive fatigue condition when compared to the control condition. While neuromuscular fatigue outcomes (i.e., endurance time, strength loss, perceived discomfort), force fluctuations, and muscle activity were similar across both the control and cognitive fatigue conditions, greater decrements in PFC activity during neuromuscular fatigue development after the cognitive fatigue condition were observed when compared to the control condition. CONCLUSION Despite similar neuromuscular outcomes, cognitive fatigue was associated with blunted PFC activation during the handgrip fatiguing exercise that may be indicative of neural adaptation with aging in an effort to maintain motor performance. Examining the relationship between cognitive fatigue and neuromuscular output by imaging other motor-related brain regions are needed to provide a better understanding of age-related compensatory adaptations to perform daily tasks that involve some levels of cognitive demand and physical exercise, especially when older adults experience them sequentially.
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Affiliation(s)
- Ashley E Shortz
- Department of Environmental and Occupational Health, School of Public Health, Texas A&M University, College Station, TX, 77843, USA.
| | - Adam Pickens
- Department of Environmental and Occupational Health, School of Public Health, Texas A&M University, College Station, TX, 77843, USA.
| | - Qi Zheng
- Department of Epidemiology and Biostatistics, School of Public Health, Texas A&M University, College Station, TX, 77843, USA.
| | - Ranjana K Mehta
- Department of Environmental and Occupational Health, School of Public Health, Texas A&M University, College Station, TX, 77843, USA.
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19
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Mehta RK. Stunted PFC activity during neuromuscular control under stress with obesity. Eur J Appl Physiol 2015; 116:319-26. [DOI: 10.1007/s00421-015-3283-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Accepted: 10/15/2015] [Indexed: 12/25/2022]
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20
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Mehta RK, Cavuoto LA. The effects of obesity, age, and relative workload levels on handgrip endurance. APPLIED ERGONOMICS 2015; 46 Pt A:91-95. [PMID: 25088026 DOI: 10.1016/j.apergo.2014.07.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Revised: 06/28/2014] [Accepted: 07/13/2014] [Indexed: 06/03/2023]
Abstract
The purpose of the study was to examine obesity and age effects on handgrip endurance across a range of relative workload levels. Forty-five non-obese and obese younger and older females performed fatiguing handgrip exercises at 20, 40, 60, and 80% of relative handgrip strength. The younger obese group demonstrated ∼7% greater strength, 32% shorter endurance times, and ∼34% faster rate of strength loss, accompanied by heightened perception of effort, than the younger non-obese group. However, these obesity-related differences were not observed in the older age group. Moreover, there were no interactions between relative workload levels, obesity, and age on any of the fatigue measures. Findings obtained here suggest that work-rest schedules computed from existing force endurance prediction models may not be protective of the younger obese working population.
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Affiliation(s)
- Ranjana K Mehta
- Department of Environmental and Occupational Health, Texas A&M University, College Station, TX 77843, USA.
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21
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Impacts of obesity and stress on neuromuscular fatigue development and associated heart rate variability. Int J Obes (Lond) 2014; 39:208-13. [PMID: 25042859 DOI: 10.1038/ijo.2014.127] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 06/30/2014] [Accepted: 07/13/2014] [Indexed: 11/08/2022]
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Cortical implication in lower voluntary muscle force production in non-hypoxemic COPD patients. PLoS One 2014; 9:e100961. [PMID: 24971775 PMCID: PMC4074123 DOI: 10.1371/journal.pone.0100961] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 06/02/2014] [Indexed: 11/19/2022] Open
Abstract
Recent studies have shown that muscle alterations cannot totally explain peripheral muscle weakness in COPD. Cerebral abnormalities in COPD are well documented but have never been implicated in muscle torque production. The purpose of this study was to assess the neural correlates of quadriceps torque control in COPD patients. Fifteen patients (FEV1 54.1±3.6% predicted) and 15 age- and sex-matched healthy controls performed maximal (MVCs) and submaximal (SVCs) voluntary contractions at 10, 30 and 50% of the maximal voluntary torque of the knee extensors. Neural activity was quantified with changes in functional near-infrared spectroscopy oxyhemoglobin (fNIRS-HbO) over the contralateral primary motor (M1), primary somatosensory (S1), premotor (PMC) and prefrontal (PFC) cortical areas. In parallel to the lower muscle torque, the COPD patients showed lower increase in HbO than healthy controls over the M1 (p<0.05), PMC (p<0.05) and PFC areas (p<0.01) during MVCs. In addition, they exhibited lower HbO changes over the M1 (p<0.01), S1 (p<0.05) and PMC (p<0.01) areas during SVCs at 50% of maximal torque and altered motor control characterized by higher torque fluctuations around the target. The results show that low muscle force production is found in a context of reduced motor cortex activity, which is consistent with central nervous system involvement in COPD muscle weakness.
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Mehta RK, Parasuraman R. Neuroergonomics: a review of applications to physical and cognitive work. Front Hum Neurosci 2013; 7:889. [PMID: 24391575 PMCID: PMC3870317 DOI: 10.3389/fnhum.2013.00889] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2013] [Accepted: 12/05/2013] [Indexed: 02/04/2023] Open
Abstract
Neuroergonomics is an emerging science that is defined as the study of the human brain in relation to performance at work and in everyday settings. This paper provides a critical review of the neuroergonomic approach to evaluating physical and cognitive work, particularly in mobile settings. Neuroergonomics research employing mobile and immobile brain imaging techniques are discussed in the following areas of physical and cognitive work: (1) physical work parameters; (2) physical fatigue; (3) vigilance and mental fatigue; (4) training and neuroadaptive systems; and (5) assessment of concurrent physical and cognitive work. Finally, the integration of brain and body measurements in investigating workload and fatigue, in the context of mobile brain/body imaging ("MoBI"), is discussed.
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Affiliation(s)
- Ranjana K Mehta
- Department of Environmental and Occupational Health, School of Rural Public Healthy, Texas A&M University, College Station TX, USA
| | - Raja Parasuraman
- Center of Excellence in Neuroergonomics, Technology, and Cognition, George Mason University Fairfax, VA, USA
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