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Wang Z, Jiang T, Xu H, Wang C, Tang R. Circadian rhythm sleep loss impairs motor inhibition more than motor execution in continuous action. Sci Rep 2024; 14:18668. [PMID: 39134656 PMCID: PMC11319480 DOI: 10.1038/s41598-024-69242-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 08/02/2024] [Indexed: 08/15/2024] Open
Abstract
Under total sleep deprivation, both inhibitory and motor control are impaired. However, how circadian rhythm sleep loss caused by irregular sleep pattern affects motor inhibition and execution in continuous actions remains unknown. This study utilized a pointing task to investigate the question over 30 days. During regular trials, participants were instructed to tap on a specified location, while in countermanding trials, they were required to countermand their current action. Additionally, there was a control group performed the same task following a normal 24-h rhythm. The results indicated that the decrease in accuracy and the increase in movement time in countermanding trials were more prominent in the shift work group. In contrast, there was no significant difference in reaction time between the two groups. Notably, the shift work group outperformed the control group in terms of movement time in regular trials and radial displacement in countermanding trials. Overall, these results show that circadian rhythm sleep loss predominantly affects inhibitory control, rather than motor control, underscoring the nuanced impacts of sleep disruption on differential aspects of cognitive and motor functions.
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Affiliation(s)
- Ziying Wang
- Naval Medical Center of PLA, Naval Medical University, Shanghai, 200433, China
- Key Laboratory of Molecular Neurobiology of Ministry of Education, Naval Medical University, Shanghai, 200433, China
| | - Tingwei Jiang
- School of Social and Behavioral Sciences, Department of Psychology, Nanjing University, Nanjing, 210023, China
| | - Haodan Xu
- Naval Medical Center of PLA, Naval Medical University, Shanghai, 200433, China
- Key Laboratory of Molecular Neurobiology of Ministry of Education, Naval Medical University, Shanghai, 200433, China
| | - Chuan Wang
- Naval Medical Center of PLA, Naval Medical University, Shanghai, 200433, China.
- Key Laboratory of Molecular Neurobiology of Ministry of Education, Naval Medical University, Shanghai, 200433, China.
| | - Rixin Tang
- School of Social and Behavioral Sciences, Department of Psychology, Nanjing University, Nanjing, 210023, China.
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2
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Gerber M, Filippou K, Knappe F, Morres ID, Tzormpatzakis E, Havas E, Seelig H, Colledge F, Ludyga S, Meier M, Theodorakis Y, von Känel R, Pühse U, Hatzigeorgiadis A. Associations between grip strength, cardiorespiratory fitness, cardiovascular risk and mental health in forcibly displaced people from a Greek refugee camp. Sci Rep 2023; 13:20970. [PMID: 38017094 PMCID: PMC10684690 DOI: 10.1038/s41598-023-48032-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 11/21/2023] [Indexed: 11/30/2023] Open
Abstract
Muscular strength represents a specific component of health-related fitness. Hand grip strength is used as a simple and dynamic marker of maximum voluntary force of the hand and to estimate overall strength. Today, little is known about the relationship between grip strength and health in forcibly displaced populations. In the present study, we examined whether grip strength is associated with various health outcomes in a sample of forcibly displaced people living in a Greek refugee camp. The present analyses are part of a larger pragmatic randomized controlled trial. In this paper, cross-sectional baseline data of 143 participants (71 men, 72 women) will be presented. In addition to grip strength, the following physical and mental health outcomes were assessed: body weight and body composition, blood pressure, total cholesterol, low- and high-density lipoprotein cholesterol, triglycerides, blood glucose levels (HbA1c), post-traumatic stress disorder (PTSD) symptoms, depressive and anxiety symptoms, pain, and quality of life. Linear regression analyses were carried out to examine how grip strength is associated with the health outcomes, separately for absolute and normalized grip strength scores. Grip strength was positively and strongly associated with percentage muscle mass (normalized grip strength: Stand. B = 0.58, p < .001), whereas a negative association existed for percentage body fat (normalized grip strength: Stand. B = - 0.58, p < .001). No statistically significant associations occurred between grip strength and the other cardiovascular risk markers. In contrast, we found that participants with higher normalized grip strength reported higher levels of PTSD (normalized grip strength: Stand. B = 0.36, p < .05) and depressive symptoms (normalized grip strength: Stand. B = 0.29, p < .05). No significant association occurred between grip strength, anxiety, pain and quality of life. Measuring grip strength in forcibly displaced people can be a useful way to assess their overall muscle strength. Grip strength tests are easy to implement, and results can be used to assess the effects of specific intervention measures. Nevertheless, our results question the usefulness of grip strength as a marker of cardiovascular health and mental wellbeing in a refugee camp setting.
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Affiliation(s)
- Markus Gerber
- Department of Sport, Exercise and Health, University of Basel, Grosse Allee 6, 4052, Basel, Switzerland.
| | - Konstantinia Filippou
- Department of Physical Education and Sport Sciences, University of Thessaly, Trikala, Greece
| | - Florian Knappe
- Department of Sport, Exercise and Health, University of Basel, Grosse Allee 6, 4052, Basel, Switzerland
| | - Ioannis D Morres
- Department of Nutrition and Dietetics, University of Thessaly, Trikala, Greece
| | - Emmanouil Tzormpatzakis
- Department of Physical Education and Sport Sciences, University of Thessaly, Trikala, Greece
| | - Elsa Havas
- Department of Physical Education and Sport Sciences, University of Thessaly, Trikala, Greece
| | - Harald Seelig
- Department of Sport, Exercise and Health, University of Basel, Grosse Allee 6, 4052, Basel, Switzerland
| | - Flora Colledge
- Department of Health Sciences and Medicine, University of Lucerne, Lucerne, Switzerland
| | - Sebastian Ludyga
- Department of Sport, Exercise and Health, University of Basel, Grosse Allee 6, 4052, Basel, Switzerland
| | - Marianne Meier
- Interdisciplinary Center for Gender Studies, University of Bern, Bern, Switzerland
| | - Yannis Theodorakis
- Department of Physical Education and Sport Sciences, University of Thessaly, Trikala, Greece
| | - Roland von Känel
- Department of Consultation-Liaison Psychiatry and Psychosomatic Medicine, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Uwe Pühse
- Department of Sport, Exercise and Health, University of Basel, Grosse Allee 6, 4052, Basel, Switzerland
| | - Antonis Hatzigeorgiadis
- Department of Physical Education and Sport Sciences, University of Thessaly, Trikala, Greece
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Iester C, Biggio M, Cutini S, Brigadoi S, Papaxanthis C, Brichetto G, Bove M, Bonzano L. Time-of-day influences resting-state functional cortical connectivity. Front Neurosci 2023; 17:1192674. [PMID: 37325041 PMCID: PMC10264597 DOI: 10.3389/fnins.2023.1192674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 05/12/2023] [Indexed: 06/17/2023] Open
Abstract
Time-of-day is rarely considered during experimental protocols investigating motor behavior and neural activity. The goal of this work was to investigate differences in functional cortical connectivity at rest linked to the time of the day using functional Near-Infrared Spectroscopy (fNIRS). Since resting-state brain is shown to be a succession of cognitive, emotional, perceptual, and motor processes that can be both conscious and nonconscious, we studied self-generated thought with the goal to help in understanding brain dynamics. We used the New-York Cognition Questionnaire (NYC-Q) for retrospective introspection to explore a possible relationship between the ongoing experience and the brain at resting-state to gather information about the overall ongoing experience of subjects. We found differences in resting-state functional connectivity in the inter-hemispheric parietal cortices, which was significantly greater in the morning than in the afternoon, whilst the intra-hemispheric fronto-parietal functional connectivity was significantly greater in the afternoon than in the morning. When we administered the NYC-Q we found that the score of the question 27 ("during RS acquisition my thoughts were like a television program or film") was significantly greater in the afternoon with respect to the morning. High scores in question 27 point to a form of thought based on imagery. It is conceivable to think that the unique relationship found between NYC-Q question 27 and the fronto-parietal functional connectivity might be related to a mental imagery process during resting-state in the afternoon.
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Affiliation(s)
- Costanza Iester
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
| | - Monica Biggio
- Department of Experimental Medicine, Section of Human Physiology, University of Genoa, Genoa, Italy
| | - Simone Cutini
- Department of Developmental and Social Psychology, University of Padova, Padua, Italy
| | - Sabrina Brigadoi
- Department of Developmental and Social Psychology, University of Padova, Padua, Italy
| | - Charalambos Papaxanthis
- INSERM UMR1093-CAPS, Université Bourgogne Franche-Comté, UFR des Sciences du Sport, Dijon, France
| | - Giampaolo Brichetto
- Italian Multiple Sclerosis Foundation, Scientific Research Area, Genoa, Italy
| | - Marco Bove
- Department of Experimental Medicine, Section of Human Physiology, University of Genoa, Genoa, Italy
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy
| | - Laura Bonzano
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genoa, Genoa, Italy
- IRCCS Ospedale Policlinico San Martino, Genoa, Italy
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Robles-González L, Ramírez Maldonado M, Alcalá-Escamilla JC, Jurado-Fasoli L, Miras-Moreno S, Soriano MA, García-Ramos A, Ruiz JR, Amaro-Gahete FJ. Caffeine ingestion attenuates diurnal variation of lower-body ballistic performance in resistance-trained women. Eur J Sport Sci 2023; 23:381-392. [PMID: 35109780 DOI: 10.1080/17461391.2022.2038274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
ABSTRACTThe present study investigates the effect of an acute intake of caffeine on the diurnal variation of neuromuscular performance in resistance-trained women. A total of 15 resistance-trained women participated in the current triple-blind, placebo-controlled, crossover experimental study. We assessed neuromuscular performance (i.e. ballistic (countermovement jump [CMJ] height and bench press throw [BPT] peak velocity), maximal strength (squat and bench press [BP] one-repetition maximum [1RM]), and strength-endurance [average velocity of the set during squat and number of repetitions-to-failure in BP]) four times at within 7 days. The participants ingested an acute dose of caffeine (3 mg/kg) or a placebo at 9-11 am and/or 17-19 pm. CMJ height (P = .016) and BP peak velocity (P = .012) were higher in the afternoon than in the morning. Compared to placebo, caffeine intake increased CMJ height by 3.1% in the morning and 1.6% in the afternoon (P = .035), but it had no effect on BPT peak velocity (P = .381). Maximal strength and strength-endurance performances were not affected by the time-of-day or caffeine intake (all P > .3). No significant interaction (time-of-day x substance) was observed in any of the above-mentioned outcomes (all P > .1). In conclusion, an acute dose of caffeine in the morning was effective to restore CMJ performance to levels found in the afternoon, while this effect was not observed neither in BPTpeak velocity nor in lower- and upper-body maximal strength and strength-endurance performance. Moreover, lower- and upper-body ballistic performance were greater in the afternoon than in the morning in resistance-trained women, while the acute intake of caffeine was only effective to increase CMJ height.HighlightsBallistic performance is probably higher in the afternoon than in the morning in resistance-trained women.An acute intake of caffeine is effective to increase countermovement jump performance.The ingestion of an acute dose of caffeine in the morning restored countermovement jump performance to levels found in the afternoon.
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Affiliation(s)
- Lidia Robles-González
- Department of Physiology, Faculty of Medicine, University of Granada, Granada, Spain.,PROFITH "PROmoting FITness and Health through physical activity" Research Group, Department of Physical Education and Sport, Faculty of Sport Sciences, Sport and Health University Research Institute (iMUDS), University of Granada, Granada, Spain
| | - Mauricio Ramírez Maldonado
- PROFITH "PROmoting FITness and Health through physical activity" Research Group, Department of Physical Education and Sport, Faculty of Sport Sciences, Sport and Health University Research Institute (iMUDS), University of Granada, Granada, Spain
| | - Juan Carlos Alcalá-Escamilla
- PROFITH "PROmoting FITness and Health through physical activity" Research Group, Department of Physical Education and Sport, Faculty of Sport Sciences, Sport and Health University Research Institute (iMUDS), University of Granada, Granada, Spain
| | - Lucas Jurado-Fasoli
- Department of Physiology, Faculty of Medicine, University of Granada, Granada, Spain.,PROFITH "PROmoting FITness and Health through physical activity" Research Group, Department of Physical Education and Sport, Faculty of Sport Sciences, Sport and Health University Research Institute (iMUDS), University of Granada, Granada, Spain
| | - Sergio Miras-Moreno
- Department of Physical Education and Sport, Faculty of Sport Sciences, University of Granada, Granada, Spain
| | - Marcos A Soriano
- Exercise Physiology Laboratory, Camilo José Cela University, Madrid, Spain.,Strength Training & Neuromuscular, Performance Research Group, Camilo José Cela University, Madrid, Spain
| | - Amador García-Ramos
- Department of Physical Education and Sport, Faculty of Sport Sciences, University of Granada, Granada, Spain.,Department of Sports Sciences and Physical Conditioning, Faculty of Education, Universidad Católica de la Santísima Concepción, Concepción, Chile
| | - Jonatan R Ruiz
- PROFITH "PROmoting FITness and Health through physical activity" Research Group, Department of Physical Education and Sport, Faculty of Sport Sciences, Sport and Health University Research Institute (iMUDS), University of Granada, Granada, Spain
| | - Francisco J Amaro-Gahete
- Department of Physiology, Faculty of Medicine, University of Granada, Granada, Spain.,PROFITH "PROmoting FITness and Health through physical activity" Research Group, Department of Physical Education and Sport, Faculty of Sport Sciences, Sport and Health University Research Institute (iMUDS), University of Granada, Granada, Spain
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5
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Sleep Deprivation Influences Trial-to-Trial Transfer but Not Task Performance. J Clin Med 2022; 11:jcm11195513. [PMID: 36233381 PMCID: PMC9571000 DOI: 10.3390/jcm11195513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 09/12/2022] [Accepted: 09/14/2022] [Indexed: 11/16/2022] Open
Abstract
Previous research has shown that sleep deprivation can affect emotions and some cognitive functions. However, research on how sleep deprivation influences the visuomotor memory have rarely been reported. In the current study, a Fitts’ Law task was used to investigate how movement and the visuomotor memory are affected under the condition of sleep deprivation. Experiment 1 had 36 participants (15 males, mean age = 21.61 years) complete the same Fitts’ Law task 10 days apart under standard conditions. Experiment 2 had five participants (three males, mean age = 27.2 years) complete the task after 7 days of sleep deprivation, then complete it again after 10 days without sleep deprivation. Experiment 1 demonstrated the stability of the trial-to-trial effects. Experiment 2 showed that the previous trial (n) exerted no effect on the current trial (n + 1) under the conditions of sleep deprivation (p = 0.672). However, the effect was observed after 10 days without sleep deprivation (p = 0.013). This suggests that sleep deprivation did not affect task performance but influenced the transfer of the trial history. Future studies are required to investigate the effect of sleep deprivation with more participants.
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6
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Laurent A, Plamondon R, Begon M. Reliability of the kinematic theory parameters during handwriting tasks on a vertical setup. Biomed Signal Process Control 2022. [DOI: 10.1016/j.bspc.2021.103157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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7
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Knaier R, Qian J, Roth R, Infanger D, Notter T, Wang W, Cajochen C, Scheer FA. Diurnal Variation in Maximum Endurance and Maximum Strength Performance: A Systematic Review and Meta-analysis. Med Sci Sports Exerc 2022; 54:169-180. [PMID: 34431827 PMCID: PMC10308487 DOI: 10.1249/mss.0000000000002773] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
INTRODUCTION Diurnal variations in physical performance can affect athletes' success in competitive sports depending on whether the time of peak performance concurs with the time of competition. The purpose of this systematic review was to investigate the diurnal variation in maximum endurance and strength performance. METHODS The databases PubMed, EMBASE, and Web of Science were searched from inception to November 2020. The search string was externally reviewed according to PRESS guidelines, and the review was conducted in accordance to PRISMA guidelines and registered beforehand on PROSPERO. Eligibility criteria were that 1) the studies included humans and 2) any kind of maximum endurance or maximum strength test was performed at 3) a minimum of three different times of the day. There were no restrictions regarding study design, participants' sex, age, or fitness levels. RESULTS From 10,460 screened articles, 63 articles met all three inclusion criteria. Meta-analysis on the harmonizable 29 studies provided evidence for diurnal variations in physical performance. In detail, the overall effect sizes (95% confidence intervals) were 0.23 (0.05-0.40), 0.73 (0.37-1.09), 0.39 (0.18-0.60), and 0.79 (0.28-1.30) for endurance exercise tests, maximum power output in the Wingate test, handgrip strength, and jump height, respectively, all in favor of higher performance in the evening. The overall risk of bias in individual studies was moderately high. CONCLUSIONS There is strong evidence that anaerobic power and jump height are maximal between 1300 and 2000 h. There is some evidence that handgrip strength peaks between 1400 and 2100 h, but only little evidence that there is a time of peak performance in maximum endurance.
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Affiliation(s)
- Raphael Knaier
- Division of Sleep Medicine, Harvard Medical School, Boston, MA
- Medical Chronobiology Program, Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women’s Hospital, Boston, MA
| | - Jingyi Qian
- Division of Sleep Medicine, Harvard Medical School, Boston, MA
- Medical Chronobiology Program, Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women’s Hospital, Boston, MA
| | - Ralf Roth
- Department of Sport, Exercise and Health, Faculty of Medicine, University of Basel, Basel, Switzerland
| | - Denis Infanger
- Department of Sport, Exercise and Health, Faculty of Medicine, University of Basel, Basel, Switzerland
| | - Timo Notter
- Department of Sport, Exercise and Health, Faculty of Medicine, University of Basel, Basel, Switzerland
| | - Wei Wang
- Division of Sleep Medicine, Harvard Medical School, Boston, MA
| | - Christian Cajochen
- Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, Switzerland
- Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, Switzerland
| | - Frank A.J.L. Scheer
- Division of Sleep Medicine, Harvard Medical School, Boston, MA
- Medical Chronobiology Program, Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women’s Hospital, Boston, MA
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Mahdavi N, Faradmal J, Dianat I, Heidarimoghadam R, Khotanlou H. Investigation of hand muscle fatigue and its influential factors in manual tasks. INTERNATIONAL JOURNAL OF OCCUPATIONAL SAFETY AND ERGONOMICS 2021; 28:1911-1923. [PMID: 33292064 DOI: 10.1080/10803548.2020.1860429] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Muscle fatigue (MF) can lead to musculoskeletal disorders (MSDs) in the long term; however, it can be managed if the causes are well known. This study aimed to examine the grip force (GF) and grip fatigue (GFa) of employees with light, moderate and heavy manual tasks using a dynamometer and find their possible relationship with other factors. The nature of heavy manual tasks led to more experience of GFa and GF of the right hand. Moreover, the equal need for both hands in occupations with light and moderate manual tasks is the reason for more GFa in the left hand. In this primary study, the height, weight and age of subjects and their exposure to vibration had a decisive effect on GF. In order to determine the accurate effects of the aforementioned risk factors on MF, it is recommended for future studies to be performed on larger populations.
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Affiliation(s)
- Neda Mahdavi
- Department of Ergonomics, Hamadan University of Medical Sciences, Iran
| | - Javad Faradmal
- Department of Ergonomics, Hamadan University of Medical Sciences, Iran
| | - Iman Dianat
- Department of Ergonomics, Tabriz University of Medical Sciences, Iran
| | | | - Hassan Khotanlou
- Department of Computer Engineering, Bu-Ali Sina University, Iran
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Temporal organisation of the brain's intrinsic motor network: The relationship with circadian phenotype and motor performance. Neuroimage 2021; 232:117840. [PMID: 33577933 PMCID: PMC8214225 DOI: 10.1016/j.neuroimage.2021.117840] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 01/27/2021] [Accepted: 02/02/2021] [Indexed: 11/20/2022] Open
Abstract
Background Functional connectivity (FC) of the motor network (MN) is often used to investigate how intrinsic properties of the brain are associated with motor abilities and performance. In addition, the MN is a key feature in clinical work to map the recovery after stroke and aid the understanding of neurodegenerative disorders. Time of day variation and individual differences in circadian timing, however, have not yet been considered collectively when looking at FC. Methods A total of 33 healthy, right handed individuals (13 male, 23.1 ± 4.2 years) took part in the study. Actigraphy, sleep diaries and circadian phase markers (dim light melatonin onset and cortisol awakening response) were used to determine early (ECP, n = 13) and late (LCP, n = 20) circadian phenotype groups. Resting state functional MRI testing sessions were conducted at 14:00 h, 20:00 h and 08:00 h and preceded by a maximum voluntary contraction test for isometric grip strength to measure motor performance. Results Significant differences in FC of the MN between ECPs and LCPs were found, as well as significant variations between different times of day. A higher amplitude in diurnal variation of FC and performance was observed in LCPs compared to ECPs, with the morning being most significantly affected. Overall, lower FC was significantly associated with poorer motor performance. Discussion Our findings uncover intrinsic differences between times of day and circadian phenotype groups. This suggests that central mechanisms contribute to diurnal variation in motor performance and the functional integrity of the MN at rest influences the ability to perform in a motor task.
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Douglas CM, Hesketh SJ, Esser KA. Time of Day and Muscle Strength: A Circadian Output? Physiology (Bethesda) 2021; 36:44-51. [PMID: 33325817 PMCID: PMC8425416 DOI: 10.1152/physiol.00030.2020] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 10/11/2020] [Accepted: 10/12/2020] [Indexed: 11/22/2022] Open
Abstract
For more than 20 years, physiologists have observed a morning-to-evening increase in human muscle strength. Recent data suggest that time-of-day differences are the result of intrinsic, nonneural, muscle factors. We evaluate circadian clock data sets from human and mouse circadian studies and highlight possible mechanisms through which the muscle circadian clock may contribute to time-of-day muscle strength outcomes.
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Affiliation(s)
- Collin M Douglas
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, FloridaMyology Institute, University of Florida, Gainesville, Florida
| | - Stuart J Hesketh
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, FloridaMyology Institute, University of Florida, Gainesville, Florida
| | - Karyn A Esser
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, FloridaMyology Institute, University of Florida, Gainesville, Florida
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11
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Knaier R, Infanger D, Cajochen C, Schmidt-Trucksaess A, Faude O, Roth R. Diurnal and day-to-day variations in isometric and isokinetic strength. Chronobiol Int 2019; 36:1537-1549. [PMID: 31476879 DOI: 10.1080/07420528.2019.1658596] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Time-of-day effects in strength performance have been extensively investigated due to their relevance in competitive sports. However, most studies use large measurement intervals making it difficult to monitor potential performance changes throughout the day. Furthermore, previous studies have exclusively focused on how the time of day affects strength on a group level and ignored the individual differences in the times of peak performance. Therefore, the main purpose of this study was to investigate the diurnal and day-to-day variations in isometric and isokinetic leg, arm and trunk strength over six different times of the day. Following a familiarization test, 19 trained males (age: 24.1 ± 2.5 years) performed isometric and isokinetic strength assessments at six different times of the day (7:00, 10:00, 13:00, 16:00, 19:00, and 21:00) with an isokinetic dynamometer. An eighth test session was performed at the same time of the day as the seventh test session to investigate the day-to-day variations and the difference between diurnal and day-to-day variations were compared. All tests were separated by at least 48 h. The start time for the first session was randomized. The mean maximum isometric leg strength was 5.85 ± 0.80 N.kg-1 and 4.99 ± 0.78 N.kg-1at the peak and at the nadir of the day, respectively. The mean difference (95% CI) was 0.86 ± 0.47 N.kg-1 (0.62; 1.10) for the diurnal variation and 0.30 ± 0.42 N.kg-1 (0.09; 0.52) for the day-to-day variation. The mean maximum isometric arm strength was 1.68 ± 0.33 N.kg-1 at the peak and 1.46 ± 0.19 N.kg-1 at the nadir of the day, respectively. The mean difference (95% CI) was 0.21 ± 0.16 N.kg-1 (0.14; 0.29) for the diurnal variation and 0.06 ± 0.05 N.kg-1 (0.03; 0.08) for the day-to-day variation. The linear mixed-effects model showed little evidence for differences in isometric leg strength between the different times of the day (all p-values >0.983). The present study demonstrated that diurnal variations in leg and arm strength are nearly three times higher than the day-to-day variations, but there was only little evidence for a time-of-day effect on a group level. The diurnal variations observed herein without time-of-day effects are suggestive that individuals achieve their peak performance at different times of the day. Therefore, performance tests should be carried out at the same time of the day to ensure comparability. Furthermore, depending on the difference between the time of competition and the time of peak performance, as well as the individual magnitude in diurnal variation, some athletes can have a clear disadvantage.Abbreviation: 95% CI, 95% confidence interval; SD, standard deviation; ICC, intraclass correlation coefficient.
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Affiliation(s)
- Raphael Knaier
- Department of Sport, Exercise and Health, Faculty of Medicine, University of Basel , Basel , Switzerland
| | - Denis Infanger
- Department of Sport, Exercise and Health, Faculty of Medicine, University of Basel , Basel , Switzerland
| | - Christian Cajochen
- Centre for Chronobiology, Psychiatric Hospital of the University of Basel , Basel , Switzerland.,Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel , Basel , Switzerland
| | - Arno Schmidt-Trucksaess
- Department of Sport, Exercise and Health, Faculty of Medicine, University of Basel , Basel , Switzerland
| | - Oliver Faude
- Department of Sport, Exercise and Health, Faculty of Medicine, University of Basel , Basel , Switzerland
| | - Ralf Roth
- Department of Sport, Exercise and Health, Faculty of Medicine, University of Basel , Basel , Switzerland
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12
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Dynamic signatures: A review of dynamic feature variation and forensic methodology. Forensic Sci Int 2018; 291:216-229. [DOI: 10.1016/j.forsciint.2018.08.021] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 08/20/2018] [Indexed: 11/19/2022]
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13
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Cocking S, Cable NT, Wilson MG, Green DJ, Thijssen DHJ, Jones H. Conduit Artery Diameter During Exercise Is Enhanced After Local, but Not Remote, Ischemic Preconditioning. Front Physiol 2018; 9:435. [PMID: 29740345 PMCID: PMC5928322 DOI: 10.3389/fphys.2018.00435] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 04/06/2018] [Indexed: 12/18/2022] Open
Abstract
Introduction: The ability of ischemic preconditioning (IPC) to enhance exercise capacity may be mediated through altering exercise-induced blood flow and/or vascular function. This study investigated the hypothesis that (local) IPC enhances exercise-induced blood flow responses and prevents decreases in vascular function following exercise. Methods: Eighteen healthy, recreationally trained, male participants (mean ±SD: age 32 ± 8 years; BMI 24.2 ± 2.3; blood pressure 122 ± 10/72 ± 8 mmHg; resting HR 58 ± 9 beats min-1) received IPC (220 mmHg; 4 × 5-min bilateral arms), REMOTE IPC (220 mmHg; 4 × 5-min bilateral legs), or SHAM (20 mmHg; 4 × 5-min bilateral arms) in a counterbalanced order prior to 30-min of submaximal (25% maximal voluntary contraction) unilateral rhythmic handgrip exercise. Brachial artery diameter and blood flow were assessed every 5-min throughout the 30-min submaximal exercise using high resolution ultrasonography. Pre- and post-exercise vascular function was measured using flow-mediated dilation (FMD). Results: IPC resulted in enlarged brachial artery diameter during exercise [0.016 cm (0.003–0.03 cm), P = 0.015] compared to REMOTE IPC, but blood flow during exercise was similar between conditions (P > 0.05). Blood flow (l/min) increased throughout exercise (time: P < 0.005), but there was no main effect of condition (P = 0.29) or condition ∗ time interaction (P = 0.83). Post-exercise FMD was similar between conditions (P > 0.05). Conclusion: Our data show that local (but not remote) IPC, performed as a strategy prior to exercise, enhanced exercise-induced conduit artery diameter dilation, but these changes do not translate into increased blood flow during exercise nor impact post-exercise vascular function.
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Affiliation(s)
- Scott Cocking
- Athlete Health and Performance Research Centre, Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Qatar.,Research Institute for Sport and Exercise Science, Liverpool John Moores University, Liverpool, United Kingdom
| | - N T Cable
- Department of Sport Science, Aspire Academy, Doha, Qatar.,School of Sport, Exercise and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Mathew G Wilson
- Athlete Health and Performance Research Centre, Aspetar Orthopaedic and Sports Medicine Hospital, Doha, Qatar.,Research Institute for Sport and Exercise Science, Liverpool John Moores University, Liverpool, United Kingdom
| | - Daniel J Green
- Research Institute for Sport and Exercise Science, Liverpool John Moores University, Liverpool, United Kingdom.,Sport and Exercise Science, School of Human Sciences, Faculty of Science, The University of Western Australia, Crawley, WA, Australia
| | - Dick H J Thijssen
- Research Institute for Sport and Exercise Science, Liverpool John Moores University, Liverpool, United Kingdom.,Department of Physiology, Radboud University Medical Center, Radboud Institute for Health Sciences, Nijmegen, Netherlands
| | - Helen Jones
- Research Institute for Sport and Exercise Science, Liverpool John Moores University, Liverpool, United Kingdom
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14
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Gatouillat A, Dumortier A, Perera S, Badr Y, Gehin C, Sejdić E. Analysis of the pen pressure and grip force signal during basic drawing tasks: The timing and speed changes impact drawing characteristics. Comput Biol Med 2017; 87:124-131. [PMID: 28582693 DOI: 10.1016/j.compbiomed.2017.05.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Revised: 05/18/2017] [Accepted: 05/19/2017] [Indexed: 11/19/2022]
Abstract
Writing is a complex fine and trained motor skill, involving complex biomechanical and cognitive processes. In this paper, we propose the study of writing kinetics using three angles: the pen-tip normal force, the total grip force signal and eventually writing quality assessment. In order to collect writing kinetics data, we designed a sensor collecting these characteristics simultaneously. Ten healthy right-handed adults were recruited and were asked to perform four tasks: first, they were instructed to draw circles at a speed they considered comfortable; they then were instructed to draw circles at a speed they regarded as fast; afterwards, they repeated the comfortable task compelled to follow the rhythm of a metronome; and eventually they performed the fast task under the same timing constraints. Statistical differences between the tasks were computed, and while pen-tip normal force and total grip force signal were not impacted by the changes introduced in each task, writing quality features were affected by both the speed changes and timing constraint changes. This verifies the already-studied speed-accuracy trade-off and suggest the existence of a timing constraints-accuracy trade-off.
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Affiliation(s)
| | - Antoine Dumortier
- Department of Electrical and Computer Engineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, USA
| | - Subashan Perera
- Department of Medicine, Division of Geriatric Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Youakim Badr
- Univ Lyon, INSA-Lyon, LIRIS, UMR5205, F-69621, France
| | | | - Ervin Sejdić
- Department of Electrical and Computer Engineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, PA, USA.
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15
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Yung M, Wells RP. Sensitivity, reliability and the effects of diurnal variation on a test battery of field usable upper limb fatigue measures. ERGONOMICS 2017; 60:923-939. [PMID: 27691721 DOI: 10.1080/00140139.2016.1243734] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Fatigue has been linked to deficits in production quality and productivity and, if of long duration, work-related musculoskeletal disorders. It may thus be a useful risk indicator and design and evaluation tool. However, there is limited information on the test-retest reliability, the sensitivity and the effects of diurnal fluctuation on field usable fatigue measures. This study reports on an evaluation of 11 measurement tools and their 14 parameters. Eight measures were found to have test-retest ICC values greater than 0.8. Four measures were particularly responsive during an intermittent fatiguing condition. However, two responsive measures demonstrated rhythmic behaviour, with significant time effects from 08:00 to mid-afternoon and early evening. Action tremor, muscle mechanomyography and perceived fatigue were found to be most reliable and most responsive; but additional analytical considerations might be required when interpreting daylong responses of MMG and action tremor. Practitioner Summary: This paper presents findings from test-retest and daylong reliability and responsiveness evaluations of 11 fatigue measures. This paper suggests that action tremor, muscle mechanomyography and perceived fatigue were most reliable and most responsive. However, mechanomyography and action tremor may be susceptible to diurnal changes.
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Affiliation(s)
- Marcus Yung
- a Department of Kinesiology , University of Waterloo , Waterloo , Canada
| | - Richard P Wells
- a Department of Kinesiology , University of Waterloo , Waterloo , Canada
- b Centre of Research Expertise for the Prevention of Musculoskeletal Disorders , University of Waterloo , Waterloo , Canada
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16
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Knaier R, Schäfer J, Rossmeissl A, Klenk C, Hanssen H, Höchsmann C, Cajochen C, Schmidt-Trucksäss A. Effects of bright and blue light on acoustic reaction time and maximum handgrip strength in male athletes: a randomized controlled trial. Eur J Appl Physiol 2017; 117:1689-1696. [PMID: 28597081 DOI: 10.1007/s00421-017-3659-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 05/29/2017] [Indexed: 11/26/2022]
Abstract
PURPOSE To assess which type of evening light exposure has the greatest effect on reaction time and maximum handgrip strength. These were pre-specified secondary outcomes in a trial which primarily investigated the influence of light on cycling performance. METHODS Seventy-four male athletes were allocated at random to either bright light (BRIGHT), monochromatic blue light (BLUE), or a control condition (CONTROL). Light exposure lasted for 60 min and started 17 h after the individual midpoint of sleep. Reaction time, handgrip strength, and melatonin levels were measured before and after the light exposure. We used analysis of covariance to compare the groups with respect to the investigated outcomes. RESULTS Two participants had to be excluded retrospectively. The remaining 72 participants had a median age of 23 years. The adjusted difference in reaction time was -1 ms [95% confidence interval (CI) -8, 6] for participants in BRIGHT and 2 ms (95% CI -5, 9) for participants in BLUE, both relative to participants in CONTROL. The adjusted difference in handgrip strength was 0.9 kg (95% CI -1.5, 3.3) for participants in BRIGHT and -0.3 kg (95% CI -2.7, 2.0) for participants in BLUE, both relative to participants in CONTROL. After the light exposure, 17% of participants in BRIGHT, 22% in BLUE, and 29% in CONTROL showed melatonin concentrations of 2 pg/ml or higher. CONCLUSIONS The results suggest that bright light might reduce melatonin levels but neither bright nor blue light exposure in the evening seem to improve reaction time or handgrip strength in athletes.
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Affiliation(s)
- Raphael Knaier
- Division Sports and Exercise Medicine, Department of Sport, Exercise and Health, University of Basel, Birsstrasse 320 B, 4052, Basel, Switzerland.
| | - Juliane Schäfer
- Division Sports and Exercise Medicine, Department of Sport, Exercise and Health, University of Basel, Birsstrasse 320 B, 4052, Basel, Switzerland
- Basel Institute for Clinical Epidemiology and Biostatistics, University Hospital Basel, 4031, Basel, Switzerland
| | - Anja Rossmeissl
- Division Sports and Exercise Medicine, Department of Sport, Exercise and Health, University of Basel, Birsstrasse 320 B, 4052, Basel, Switzerland
| | - Christopher Klenk
- Division Sports and Exercise Medicine, Department of Sport, Exercise and Health, University of Basel, Birsstrasse 320 B, 4052, Basel, Switzerland
| | - Henner Hanssen
- Division Sports and Exercise Medicine, Department of Sport, Exercise and Health, University of Basel, Birsstrasse 320 B, 4052, Basel, Switzerland
| | - Christoph Höchsmann
- Division Sports and Exercise Medicine, Department of Sport, Exercise and Health, University of Basel, Birsstrasse 320 B, 4052, Basel, Switzerland
| | - Christian Cajochen
- Centre for Chronobiology, Psychiatric Hospital of the University of Basel, 4056, Basel, Switzerland
- Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, Switzerland
| | - Arno Schmidt-Trucksäss
- Division Sports and Exercise Medicine, Department of Sport, Exercise and Health, University of Basel, Birsstrasse 320 B, 4052, Basel, Switzerland
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17
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Gueugneau N, Pozzo T, Darlot C, Papaxanthis C. Daily modulation of the speed-accuracy trade-off. Neuroscience 2017; 356:142-150. [PMID: 28499976 DOI: 10.1016/j.neuroscience.2017.04.043] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 04/25/2017] [Accepted: 04/27/2017] [Indexed: 10/19/2022]
Abstract
Goal-oriented arm movements are characterized by a balance between speed and accuracy. The relation between speed and accuracy has been formalized by Fitts' law and predicts a linear increase in movement duration with task constraints. Up to now this relation has been investigated on a short-time scale only, that is during a single experimental session, although chronobiological studies report that the motor system is shaped by circadian rhythms. Here, we examine whether the speed-accuracy trade-off could vary during the day. Healthy adults carried out arm-pointing movements as accurately and fast as possible toward targets of different sizes at various hours of the day, and variations in Fitts' law parameters were scrutinized. To investigate whether the potential modulation of the speed-accuracy trade-off has peripheral and/or central origins, a motor imagery paradigm was used as well. Results indicated a daily (circadian-like) variation for the durations of both executed and mentally simulated movements, in strictly controlled accuracy conditions. While Fitts' law was held for the whole sessions of the day, the slope of the relation between movement duration and task difficulty expressed a clear modulation, with the lowest values in the afternoon. This variation of the speed-accuracy trade-off in executed and mental movements suggests that, beyond execution parameters, motor planning mechanisms are modulated during the day. Daily update of forward models is discussed as a potential mechanism.
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Affiliation(s)
- Nicolas Gueugneau
- Cognition, Action et Plasticité Sensorimotrice (CAPS), INSERM UMR1093, Université de Bourgogne Franche-Comté, F-21000 Dijon, France.
| | - Thierry Pozzo
- Cognition, Action et Plasticité Sensorimotrice (CAPS), INSERM UMR1093, Université de Bourgogne Franche-Comté, F-21000 Dijon, France
| | - Christian Darlot
- Cognition, Action et Plasticité Sensorimotrice (CAPS), INSERM UMR1093, Université de Bourgogne Franche-Comté, F-21000 Dijon, France
| | - Charalambos Papaxanthis
- Cognition, Action et Plasticité Sensorimotrice (CAPS), INSERM UMR1093, Université de Bourgogne Franche-Comté, F-21000 Dijon, France
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18
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Daily update of motor predictions by physical activity. Sci Rep 2015; 5:17933. [PMID: 26632341 PMCID: PMC4668580 DOI: 10.1038/srep17933] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 11/06/2015] [Indexed: 11/08/2022] Open
Abstract
Motor prediction, i.e., the ability to predict the sensory consequences of motor commands, is critical for adapted motor behavior. Like speed or force, the accuracy of motor prediction varies in a 24-hour basis. Although the prevailing view is that basic biological markers regulate this circadian modulation, behavioral factors such as physical activity, itself modulated by the alternation of night and day, can also regulate motor prediction. Here, we propose that physical activity updates motor prediction on a daily basis. We tested our hypothesis by up- and down-regulating physical activity via arm-immobilization and high-intensity training, respectively. Motor prediction was assessed by measuring the timing differences between actual and mental arm movements. Results show that although mental movement time was modulated during the day when the arm was unconstrained, it remained constant when the arm was immobilized. Additionally, increase of physical activity, via release from immobilization or intense bout of training, significantly reduced mental movement time. Finally, mental and actual times were similar in the afternoon in the unconstrained condition, indicating that predicted and actual movements match after sufficient amount of physical activity. Our study supports the view that physical activity calibrates motor predictions on a daily basis.
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19
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Improvements on neuromuscular performance with caffeine ingestion depend on the time-of-day. J Sci Med Sport 2015; 18:338-42. [DOI: 10.1016/j.jsams.2014.04.010] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Revised: 04/08/2014] [Accepted: 04/17/2014] [Indexed: 11/20/2022]
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20
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Hölzle P, Tatarau C, Hermsdörfer J. Visually guided tracking on a handheld device: can it be used to measure visuomotor skill in shift workers? HUMAN FACTORS 2014; 56:1296-1306. [PMID: 25490809 DOI: 10.1177/0018720814528005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
OBJECTIVE We introduced a new visually controlled tracking task that can be assessed on a handheld device in shift workers to evaluate time-of-day dependent modulations in visuomotor performance. BACKGROUND Tracking tasks have been used to predict performance fluctuations depending on time of day mainly under laboratory conditions. One challenge to an extended use at the actual working site is the complex and fixed test setup consisting of a test unit, a monitor, and a manipulation object, such as a joystick. METHOD Participants followed an unpredictably moving target on the screen of a handheld device with an attachable stylus. A total of 11 shift workers (age range: 20-59, mean: 33.64, standard deviation: 10.56) were tested in the morning, the evening, and the night shift in 2-hr intervals with the tracking task and indicated their fatigue levels on visual analogue scales. We evaluated tracking precision by calculating the mean spatial deviation from the target for each session. RESULTS Tracking precision was significantly influenced by the interaction between shift and session, suggesting a clear time-of-day effect of visuomotor performance under real-life conditions. Tracking performance declined during early-morning hours whereas fatigue ratings increased. CONCLUSION These findings suggest that our setup is suitable to detect time-of-day dependent performance changes in visually guided tracking. APPLICATION Our task could be used to evaluate fluctuations in visuomotor coordination, a skill that is decisive in various production steps at the actual working place to assess productivity.
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21
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Wilson TW, Heinrichs-Graham E, Becker KM. Circadian modulation of motor-related beta oscillatory responses. Neuroimage 2014; 102 Pt 2:531-9. [PMID: 25128712 DOI: 10.1016/j.neuroimage.2014.08.013] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Revised: 05/28/2014] [Accepted: 08/05/2014] [Indexed: 10/24/2022] Open
Abstract
Previous electrophysiological investigations have evaluated movement-related beta (14-28 Hz) oscillatory activity in healthy participants. These studies have described an abrupt decrease in beta activity that starts before movement onset, and a sharp increase in beta power that peaks after movement termination. These neural responses have been respectively termed the event-related beta desynchronization or pre-movement beta ERD, and the post-movement beta rebound (PMBR). Previous studies have shown that a variety of movement parameters and demographic factors (e.g., age) modulate the amplitude of these oscillatory responses, and in the current study we evaluated whether the amplitudes follow a biological temporal rhythm (e.g., circadian), as it is known that spontaneous beta levels increase from morning to afternoon in some brain areas. To this end, we used magnetoencephalography (MEG) to evaluate oscillatory activity during a right hand finger-tapping task in four participants who were recorded at three different times (09:00, 12:00, 16:00) on three consecutive days (i.e., 36 total MEG sessions). All MEG data were corrected for head motion and examined in the time-frequency domain using beamforming methods. We found a significant linear increase in beta ERD amplitude from 09:00 to 16:00 h in the left precentral gyrus, left premotor cortices, left supplementary motor area (SMA), and right precentral and postcentral gyri. In contrast, the amplitude of the PMBR was very steady across the day in all brain regions except the left SMA, which exhibited a linear increase from morning to afternoon. Finally, beta levels during the baseline period also increased from 09:00 to 16:00 in most regions of the cortical sensorimotor network. These data show that both the pre-movement beta ERD and spontaneous beta levels strongly increase from morning to afternoon in the motor cortices, which may indicate that the amplitude of the beta ERD response is determined by the spontaneous beta level during the motor planning period.
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Affiliation(s)
- Tony W Wilson
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska, Medical Center (UNMC), Omaha, NE, USA; Department of Neurological Sciences, UNMC, Omaha, NE, USA; Center for Magnetoencephalography, UNMC, Omaha, NE, USA.
| | - Elizabeth Heinrichs-Graham
- Center for Magnetoencephalography, UNMC, Omaha, NE, USA; Department of Psychology, University of Nebraska, Omaha, NE, USA
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Hölzle P, Hermsdörfer J, Vetter C. The effects of shift work and time of day on fine motor control during handwriting. ERGONOMICS 2014; 57:1488-1498. [PMID: 25026215 DOI: 10.1080/00140139.2014.935746] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
UNLABELLED Handwriting is an elaborate and highly automatised skill relying on fine motor control. In laboratory conditions handwriting kinematics are modulated by the time of day. This study investigated handwriting kinematics in a rotational shift system and assessed whether similar time of day fluctuations at the work place can be observed. Handwriting performance was measured in two tasks of different levels of complexity in 34 shift workers across morning (6:00-14:00), evening (14:00-22:00) and night shifts (22:00-6:00). Participants were tested during all three shifts in 2-h intervals with mobile testing devices. We calculated average velocity, script size and writing frequency to quantify handwriting kinematics and fluency. Average velocity and script size were significantly affected by the shift work schedule with the worst performance during morning shifts and the best performance during evening shifts. Our data are of high economic relevance as fine motor skills are indispensable for accurate and effective production at the work place. PRACTITIONER SUMMARY Handwriting is one of the most complex fine motor skills in humans, which is frequently performed in daily life. In this study, we tested handwriting repeatedly at the work place in a rotational shift system. We found slower handwriting velocity and reduced script size during morning shifts.
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Affiliation(s)
- Patricia Hölzle
- a Department of Psychiatry and Psychotherapy , Technische Universität München , Munich , Germany
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23
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Yung M, Bigelow PL, Hastings DM, Wells RP. Detecting within- and between-day manifestations of neuromuscular fatigue at work: an exploratory study. ERGONOMICS 2014; 57:1562-1573. [PMID: 24998392 DOI: 10.1080/00140139.2014.934299] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
UNLABELLED Cumulative neuromuscular fatigue may result from exposure to physically demanding work, such as repetitive and/or sustained work with insufficient recovery. The aims of this exploratory study were to develop a battery of field usable fatigue measures and to document hand/arm fatigue in physically demanding work over multiple workdays and after a weekend break. Sixteen plumbers were observed for five days and measures of handgrip force, variability, tremor and discomfort were obtained pre-, mid- and post-shift. This exploratory study demonstrated increasing fatigue of the hand/arm over the day and persistent fatigue from Tuesday to Friday, and that a number of the measures did not return to baseline values following a weekend break. The findings provide preliminary evidence of cumulative fatigue in residential plumbing and insight into neuromuscular fatigue measurement. However, further work is needed to develop and refine a set of fatigue measures to detect neuromuscular fatigue at the workplace. PRACTITIONER SUMMARY Cumulative fatigue has been linked to long-term health outcomes, including work-related musculoskeletal disorders. This paper presents findings from a physically demanding job (i.e. plumbing) revealing persistent fatigue over the work shift(s) and insufficient recovery after a weekend break, and provides insight into fatigue measurement at the workplace.
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Affiliation(s)
- Marcus Yung
- a Department of Kinesiology , University of Waterloo , Ontario , Canada
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Ghali B, Mamun KA, Chau T. Long term consistency of handwriting grip kinetics in adults. J Biomech Eng 2014; 136:1829830. [PMID: 24510237 DOI: 10.1115/1.4026641] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Accepted: 02/06/2014] [Indexed: 11/08/2022]
Abstract
While there is growing interest in clinical applications of handwriting grip kinetics, the consistency of these forces over time is not well-understood at present. In this study, we investigated the short- and long-term intra-participant consistency and inter-participant differences in grip kinetics associated with adult signature writing. Grip data were collected from 20 adult participants using a digitizing tablet and an instrumented pen. The first phase of data collection occurred over 10 separate days within a three week period. To ascertain long-term consistency, a second phase of data collection followed, one day per month over several months. In both phases, data were collected three times a day. After pre-processing and feature extraction, nonparametric statistical tests were used to compare the within-participant grip force variation between the two phases. Participant classification based on grip force features was used to determine the relative magnitude of inter-participant versus intra-participant differences. The misclassification rate for the longitudinal data were used as an indication of long term kinetic consistency. Intra-participant analysis revealed significant changes in grip kinetic features between the two phases for many participants. However, the misclassification rate, on average, remained stable, despite different demarcations of training, and testing data. This finding suggests that while signature writing grip forces may evolve over time, inter-participant kinetic differences consistently exceeds within-participant force changes in the long-term. These results bear implications on the collection, modeling and interpretation of grip kinetics in clinical applications.
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Mizuno K. Human circadian rhythms and exercise: Significance and application in real-life situations. THE JOURNAL OF PHYSICAL FITNESS AND SPORTS MEDICINE 2014. [DOI: 10.7600/jpfsm.3.307] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Juda M, Vetter C, Roenneberg T. Chronotype modulates sleep duration, sleep quality, and social jet lag in shift-workers. J Biol Rhythms 2013; 28:141-51. [PMID: 23606613 DOI: 10.1177/0748730412475042] [Citation(s) in RCA: 196] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
This study explores chronotype-dependent tolerance to the demands of working morning, evening, and night shifts in terms of social jet lag, sleep duration, and sleep disturbance. A total of 238 shift-workers were chronotyped with the Munich ChronoType Questionnaire for shift-workers (MCTQ(Shift)), which collects information about shift-dependent sleep duration and sleep timing. Additionally, 94 shift-workers also completed those items of the Sleep Questionnaire from the Standard Shift-Work Index (SSI) that assess sleep disturbances. Although all participants worked morning, evening, and night shifts, subsamples differed in rotation direction and speed. Sleep duration, social jet lag, and sleep disturbance were all significantly modulated by the interaction of chronotype and shift (mixed-model ANOVAs). Earlier chronotypes showed shortened sleep duration during night shifts, high social jet lag, as well as higher levels of sleep disturbance. A similar pattern was observed for later chronotypes during early shifts. Age itself only influenced sleep duration and quality per se, without showing interactions with shifts. We found that workers slept longer in fast, rotating shift schedules. Since chronotype changes with age, investigations on sleep behavior and circadian misalignment in shift-workers have to consider chronotype to fully understand interindividual and intraindividual variability, especially in view of the current demographic changes. Given the impact of sleep on health, our results stress the importance of chronotype both in understanding the effects of shift-work on sleep and in devising solutions to reduce shift-work-related health problems.
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Affiliation(s)
- Myriam Juda
- Institute of Medical Psychology, Centre of Chronobiology, Ludwig Maximilian University of Munich, Munich, Germany
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Abstract
This article focuses on physical performances after training at a specific time of day. To date, although the effect of time of day on aerobic performances appears to be equivocal, during anaerobic exercises, the effect of time of day has been well established with early morning nadirs and peak performances in the late afternoon. These diurnal rhythms can be influenced by several factors such as the regular training at a specific time of day. Indeed, regular training in the morning hours may increase the lower morning performances to the same or even higher level as their normal diurnal peak typically observed in the late afternoon by a greater increase of performance in the evening. However, regular training in the evening hours may increase the morning-evening (i.e., amplitude of the rhythm) difference by a greater increase of performance in the late afternoon. Therefore, adaptations to training are greater at the time of day at which training is regularly performed than at other times. Nevertheless, although modifications in resting hormones concentrations could explain this time-of-day specific adaptations, precise information on the underlying mechanisms is lacking.
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Affiliation(s)
- Hamdi Chtourou
- Research Laboratory Sports Performance Optimization, National Center of Medicine and Science in Sports (CNMSS), Tunis, Tunisia.
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28
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Portaluppi F, Smolensky MH, Haus E, Fabbian F. Relevance of Chronobiology to the Research and Clinical Practice of Neurorehabilitation. Sleep Med Clin 2012. [DOI: 10.1016/j.jsmc.2012.08.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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29
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Classifying fMRI-derived resting-state connectivity patterns according to their daily rhythmicity. Neuroimage 2012; 71:298-306. [PMID: 22906784 DOI: 10.1016/j.neuroimage.2012.08.010] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Revised: 08/05/2012] [Accepted: 08/06/2012] [Indexed: 01/09/2023] Open
Abstract
The vast majority of biological functions express rhythmic fluctuations across the 24-hour day. We investigated the degree of daily modulation across fMRI (functional Magnetic Resonance Imaging) derived resting-state data in 15 subjects by evaluating the time courses of 20 connectivity patterns over 8h (4 sessions). For each subject, we determined the chronotype, which describes the relationship between the individual circadian rhythm and the local time. We could therefore analyze the daily time course of the connectivity patterns controlling for internal time. Furthermore, as the participants' scan times were staggered as a function of their chronotype, we prevented sleep deprivation and kept time awake constant across subjects. Individual functional connectivity within each connectivity pattern was defined at each session as connectivity strength measured by a mean z-value and, in addition, as the spatial extent expressed by the number of activated voxels. Highly rhythmic connectivity patterns included two sub-systems of the Default-Mode Network (DMN) and a network extending over sensori-motor regions. The network characterized as the most stable across the day is mainly associated with processing of executive control. We conclude that the degree of daily modulation largely varies across fMRI derived resting-state connectivity patterns, ranging from highly rhythmic to stable. This finding should be considered when interpreting results from fMRI studies.
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The effect of extended wake on postural control in young adults. Exp Brain Res 2012; 221:329-35. [PMID: 22821076 DOI: 10.1007/s00221-012-3175-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Accepted: 06/28/2012] [Indexed: 10/28/2022]
Abstract
The sleep-wake cycle is a major determinant of locomotor activity in humans, and the neural and physiological processes necessary for optimum postural control may be impaired by an extension of the wake period into habitual sleep time. There is growing evidence for such a contribution from sleep-related factors, but great inconsistency in the methods used to assess this contribution, particularly in control for circadian phase position. Postural control was assessed at hourly intervals across 14 h of extended wake in nine young adult participants. Force plate parameters of medio-lateral and anterior-posterior sway, centre of pressure (CoP) trace length, area, and velocity were assessed with eyes open and eyes closed over 3-min periods. A standard measure of psychomotor vigilance was assessed concurrently under constant routine conditions. After controlling for individual differences in circadian phase position, a significant effect of extended wake was found for anterior-posterior sway and for psychomotor vigilance. These data suggest that extended wake may increase the risk of a fall or other consequences of impaired postural control.
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Mora-Rodríguez R, García Pallarés J, López-Samanes Á, Ortega JF, Fernández-Elías VE. Caffeine ingestion reverses the circadian rhythm effects on neuromuscular performance in highly resistance-trained men. PLoS One 2012; 7:e33807. [PMID: 22496767 PMCID: PMC3319538 DOI: 10.1371/journal.pone.0033807] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2012] [Accepted: 02/22/2012] [Indexed: 11/19/2022] Open
Abstract
PURPOSE To investigate whether caffeine ingestion counteracts the morning reduction in neuromuscular performance associated with the circadian rhythm pattern. METHODS Twelve highly resistance-trained men underwent a battery of neuromuscular tests under three different conditions; i) morning (10:00 a.m.) with caffeine ingestion (i.e., 3 mg kg(-1); AM(CAFF) trial); ii) morning (10:00 a.m.) with placebo ingestion (AM(PLAC) trial); and iii) afternoon (18:00 p.m.) with placebo ingestion (PM(PLAC) trial). A randomized, double-blind, crossover, placebo controlled experimental design was used, with all subjects serving as their own controls. The neuromuscular test battery consisted in the measurement of bar displacement velocity during free-weight full-squat (SQ) and bench press (BP) exercises against loads that elicit maximum strength (75% 1RM load) and muscle power adaptations (1 m s(-1) load). Isometric maximum voluntary contraction (MVC(LEG)) and isometric electrically evoked strength of the right knee (EVOK(LEG)) were measured to identify caffeine's action mechanisms. Steroid hormone levels (serum testosterone, cortisol and growth hormone) were evaluated at the beginning of each trial (PRE). In addition, plasma norepinephrine (NE) and epinephrine were measured PRE and at the end of each trial following a standardized intense (85% 1RM) 6 repetitions bout of SQ (POST). RESULTS In the PM(PLAC) trial, dynamic muscle strength and power output were significantly enhanced compared with AM(PLAC) treatment (3.0%-7.5%; p≤0.05). During AM(CAFF) trial, muscle strength and power output increased above AM(PLAC) levels (4.6%-5.7%; p≤0.05) except for BP velocity with 1 m s(-1) load (p = 0.06). During AM(CAFF), EVOK(LEG) and NE (a surrogate of maximal muscle sympathetic nerve activation) were increased above AM(PLAC) trial (14.6% and 96.8% respectively; p≤0.05). CONCLUSIONS These results indicate that caffeine ingestion reverses the morning neuromuscular declines in highly resistance-trained men, raising performance to the levels of the afternoon trial. Our electrical stimulation data, along with the NE values, suggest that caffeine increases neuromuscular performance having a direct effect in the muscle.
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RAMÍREZ C, GARCÍA A, VALDEZ P. Identification of circadian rhythms in cognitive inhibition and flexibility using a Stroop task. Sleep Biol Rhythms 2012. [DOI: 10.1111/j.1479-8425.2012.00540.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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García A, Ramírez C, Martínez B, Valdez P. Circadian rhythms in two components of executive functions: cognitive inhibition and flexibility. BIOL RHYTHM RES 2012. [DOI: 10.1080/09291016.2011.638137] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Portaluppi F. The Medical Subject Headings® thesaurus remains inaccurate and incomplete for electronic indexing and retrieval of chronobiologic references. BIOL RHYTHM RES 2011. [DOI: 10.1080/09291016.2011.613619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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Peres I, Vetter C, Blautzik J, Reiser M, Pöppel E, Meindl T, Roenneberg, T, Gutyrchik E. Chronotype Predicts Activity Patterns in the Neural Underpinnings of the Motor System During the Day. Chronobiol Int 2011; 28:883-9. [DOI: 10.3109/07420528.2011.619084] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Jasper I, Gordijn M, Häußler A, Hermsdörfer J. Circadian rhythms in handwriting kinematics and legibility. Hum Mov Sci 2011; 30:818-29. [DOI: 10.1016/j.humov.2010.04.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2010] [Revised: 04/13/2010] [Accepted: 04/19/2010] [Indexed: 01/22/2023]
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Steinborn MB, Bratzke D, Rolke B, Gordijn MCM, Beersma DGM, Ulrich R. The effect of 40 hours of constant wakefulness on number comparison performance. Chronobiol Int 2010; 27:807-25. [PMID: 20560712 DOI: 10.3109/07420521003778765] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
We investigated the effects of sleep loss and circadian rhythm on number comparison performance. Magnitude comparison of single-digits is robustly characterized by a distance effect: Close numbers (e.g., 5 versus 6) produce longer reaction times than numbers further apart (e.g., 2 versus 8). This distance effect is assumed to reflect the difficulty of a comparison process based on an analogous representation of general magnitude. Twelve male participants were required to stay awake for 40 h in a quasi-constant-routine protocol. Response speed and accuracy deteriorated between 00:00 and 06:00 h but recovered afterwards during the next day, indicating a circadian rhythm of elementary cognitive function (i.e., attention and speed of mental processing). The symbolic distance effect, however, did not increase during the nighttime, indicating that neither cumulative sleep loss nor the circadian clock prolongs numerical comparison processes. The present findings provide first evidence for a relative insensitivity of symbolic magnitude processing against the temporal variation in energy state.
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Affiliation(s)
- Michael B Steinborn
- Department of Cognitive and Biological Psychology, University of Tübingen, Tübingen, Germany
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Jasper I, Roenneberg T, Häussler A, Zierdt A, Marquardt C, Hermsdörfer J. Circadian rhythm in force tracking and in dual task costs. Chronobiol Int 2010; 27:653-73. [PMID: 20524807 DOI: 10.3109/07420521003663793] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The present study determined a circadian rhythm in force control during a visually guided tracking task under single task conditions (i.e., tracking task presented alone) and dual task conditions (i.e., tracking task together with a memory task). Nine healthy young male subjects participated in a Constant Routine protocol involving a week of regular bedtimes, a baseline night of 8 h sleep, and subsequent wakefulness of 40 h. Subjects performed an eye-hand coordination task that required tracking an unpredictable target (presented on a computer screen) by using grip force to adjust a visual feedback to the changing target. Tracking performance (both in precision and delay) were time-of-day-specific with worst performance at around 04:00 h. The dual task costs, as an index of interference of two tasks performed simultaneously, only showed a significant effect of the memory task on tracking precision during the circadian minimum. In contrast, dual task costs were close to zero during midday and absent in tracking delay. Tracking precision descriptively revealed inter-individual differences: half of the subjects maintained fairly stable performance during the 40 h of wakefulness, whereas the other half showed a clear circadian rhythmicity in tracking precision. Thus, tracking precision seems to be a sensitive parameter for conditions of divided attention and inter-individual variability during the circadian minimum, whereas tracking delay revealed neither a dichotomy of task conditions nor inter-individual differences in performance-amplitude over sessions. Nonetheless, both tracking precision and delay showed a comparable circadian rhythmicity.
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Affiliation(s)
- Isabelle Jasper
- Clinical Neuropsychology Research Group (EKN), Clinic for Neuropsychology, München-Bogenhausen Hospital, Munich, Germany.
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Gueugneau N, Papaxanthis C. Time-of-day effects on the internal simulation of motor actions: psychophysical evidence from pointing movements with the dominant and non-dominant arm. Chronobiol Int 2010; 27:620-39. [PMID: 20524805 DOI: 10.3109/07420521003664205] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
It is well known that circadian rhythms modulate human physiology and behavior at various levels. However, chronobiological data concerning mental and sensorimotor states of motor actions are still lacking in the literature. In the present study, we examined the effects of time-of-day on two important aspects of the human motor behavior: prediction and laterality. Motor prediction was experimentally investigated by means of imagined movements and laterality by comparing the difference in temporal performance between right and left arm movements. Ten healthy participants had to actually perform or to imagine performing arm-pointing movements between two targets at different hours of the day (i.e., 08:00, 11:00, 14:00, 17:00, 20:00, and 23:00 h). Executed and imagined movements were accomplished with both the right and left arm. We found that both imagined and executed arm pointing movements significantly fluctuated through the day. Furthermore, the accuracy of motor prediction, investigated by the temporal discrepancy between executed and imagined movements, was significantly better in the afternoon (i.e., 14:00, 17:00, and 20:00 h) than morning (08:00 and 11:00 h) and evening (23:00 h). Our results also revealed that laterality was not stable throughout the day. Indeed, the smallest temporal differences between the two arms appeared at 08:00 and 23:00 h, whereas the largest ones occurred at the end of the morning (11:00 h). The daily variation of motor imagery may suggest that internal predictive models are flexible entities that are continuously updated throughout the day. Likewise, the variations in temporal performance between the right and the left arm during the day may indicate a relative independence of the two body sides in terms of circadian rhythms. In general, our findings suggest that cognitive (i.e., mental imagery) and motor (i.e., laterality) states of human behavior are modulated by circadian rhythms.
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Sargent C, Ferguson SA, Darwent D, Kennaway DJ, Roach GD. THE INFLUENCE OF CIRCADIAN PHASE AND PRIOR WAKE ON NEUROMUSCULAR FUNCTION. Chronobiol Int 2010; 27:911-21. [DOI: 10.3109/07420528.2010.488901] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Hayes LD, Bickerstaff GF, Baker JS. INTERACTIONS OF CORTISOL, TESTOSTERONE, AND RESISTANCE TRAINING: INFLUENCE OF CIRCADIAN RHYTHMS. Chronobiol Int 2010; 27:675-705. [DOI: 10.3109/07420521003778773] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Valdez P, Ramírez C, García A, Talamantes J, Cortez J. CIRCADIAN AND HOMEOSTATIC VARIATION IN SUSTAINED ATTENTION. Chronobiol Int 2010; 27:393-416. [DOI: 10.3109/07420521003765861] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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