resistance induced by sleep loss? Sleep Medicine Reviews, 37, 60 – 68 . PubMed ID: 29056415 doi: 10.1016/j.smrv.2017.01.001 Sweeney , E.L. , Jeromson , S. , Hamilton , D.L. , Brooks , N.E. , & Walshe , I.H. ( 2017 ). Skeletal muscle insulin signaling and whole-body glucose metabolism
Emma L. Sweeney, Daniel J. Peart, Irene Kyza, Thomas Harkes, Jason G. Ellis and Ian H. Walshe
Melissa Skein, Rob Duffield, Geoffrey M. Minett, Alanna Snape and Alistair Murphy
This study examined the effects of overnight sleep deprivation on recovery after competitive rugby league matches.
Eleven male amateur rugby league players played 2 competitive matches, followed by either a normal night’s sleep (~8 h; CONT) or a sleep-deprived night (~0 h; SDEP) in a randomized fashion. Testing was conducted the morning of the match, immediately postmatch, 2 h postmatch, and the next morning (16 h postmatch). Measures included countermovement-jump (CMJ) distance, knee-extensor maximal voluntary contraction (MVC) and voluntary activation (VA), venous-blood creatine kinase (CK) and C-reactive protein (CRP), perceived muscle soreness, and a word–color recognition cognitive-function test. Percent change between postmatch and 16-h postmatch was reported to determine the effect of the intervention the next morning.
Large effects indicated a greater postmatch to 16-h-postmatch percentage decline in CMJ distance after SDEP than in CONT (P = .10–.16, d = 0.95–1.05). Similarly, the percentage decline in incongruent word–color reaction times was increased in SDEP trials (P = .007, d = 1.75). Measures of MVC did not differ between conditions (P = .40–.75, d = 0.13–0.33), although trends for larger percentage decline in VA were detected in SDEP (P = .19, d = 0.84). Furthermore, large effects indicated higher CK and CRP responses 16 h postmatch in SDEP than in CONT (P = .11–.87, d = 0.80–0.88).
Sleep deprivation negatively affected recovery after a rugby league match, specifically impairing CMJ distance and cognitive function. Practitioners should promote adequate postmatch sleep patterns or adjust training demands the next day to accommodate the altered physical and cognitive state after sleep deprivation.
Kazuto Omiya, Yoshihiro J Akashi, Kihei Yoneyama, Naohiko Osada, Kazuhiko Tanabe and Fumihiko Miyake
The aim of this study was to clarify the mechanism of impaired exercise tolerance in chronic sleep-restricted conditions by investigating variables related to heart-rate (HR) response to sympathetic nervous stimulation. Sixteen healthy men (mean age 21.5 years) were tested in a control state, acute sleep-loss state, and chronic sleeprestricted state. Participants underwent cardiopulmonary exercise testing in each state. Their norepinephrine (NE) concentration was measured before and immediately after exercise. Intracellular magnesium (Mg) concentration was measured in a resting state. Exercise duration was shorter and the ratio of HR response to the percentage increase in NE was higher in the chronic sleep-restricted state than in the control state. Intracellular Mg gradually decreased from control to chronic sleep restriction. There was a negative correlation between peak exercise duration and the ratios of HR response to the rate of increase in NE. Intracellular Mg was positively correlated with the ratios of HR response to the increase in NE both in control and in acute sleep loss. The authors conclude that the impaired exercise tolerance in a chronic sleep-restricted state is caused by hypersensitivity of the HR response to sympathetic nervous stimulation, which showed a compensation for decreased intracellular Mg concentration.
Hugh H.K. Fullagar, Rob Duffield, Sabrina Skorski, Aaron J. Coutts, Ross Julian and Tim Meyer
While the effects of sleep loss on performance have previously been reviewed, the effects of disturbed sleep on recovery after exercise are less reported. Specifically, the interaction between sleep and physiological and psychological recovery in team-sport athletes is not well understood. Accordingly, the aim of the current review was to examine the current evidence on the potential role sleep may play in postexercise recovery, with a tailored focus on professional team-sport athletes. Recent studies show that team-sport athletes are at high risk of poor sleep during and after competition. Although limited published data are available, these athletes also appear particularly susceptible to reductions in both sleep quality and sleep duration after night competition and periods of heavy training. However, studies examining the relationship between sleep and recovery in such situations are lacking. Indeed, further observational sleep studies in team-sport athletes are required to confirm these concerns. Naps, sleep extension, and sleep-hygiene practices appear advantageous to performance; however, future proof-of-concept studies are now required to determine the efficacy of these interventions on postexercise recovery. Moreover, more research is required to understand how sleep interacts with numerous recovery responses in team-sport environments. This is pertinent given the regularity with which these teams encounter challenging scenarios during the course of a season. Therefore, this review examines the factors that compromise sleep during a season and after competition and discusses strategies that may help improve sleep in team-sport athletes.
William M. Adams, Yuri Hosokawa, Robert A. Huggins, Stephanie M. Mazerolle and Douglas J. Casa
Evidence-based best practices for the recognition and treatment of exertional heat stroke (EHS) indicate that rectal thermometry and immediate, aggressive cooling via cold-water immersion ensure survival from this medical condition. However, little is known about the recovery, medical follow-up, and return to activity after an athlete has suffered EHS.
To highlight the transfer of evidenced-based research into clinical practice by chronicling the treatment, recovery, and return to activity of a runner who suffered an EHS during a warm-weather road race.
Warm-weather road race.
53-y-old recreationally active man.
A runner’s treatment, recovery, and return to activity from EHS and 2014 Falmouth Road Race performance.
Runner’s perceptions and experiences with EHS, body temperature, heart rate, hydration status, exercise intensity.
The runner successfully completed the 2014 Falmouth Road Race without incident of EHS. Four dominant themes emerged from the data: predisposing factors, ideal treatment, lack of medical follow-up, and patient education. The first theme identified 3 predisposing factors that contributed to the runner’s EHS: hydration, sleep loss, and lack of heat acclimatization. The runner received ideal treatment using evidence-based best practices. A lack of long-term medical care following the EHS with no guidance on the runner’s return to full activity was observed. The runner knew very little about EHS before the 2013 race, which drove him to seek knowledge as to why he suffered EHS. Using this newly learned information, he successfully completed the 2014 Falmouth Road Race without incident.
This case supports prior literature examining the factors that predispose individuals to EHS. Although evidence-based best practices regarding prompt recognition and treatment of EHS ensure survival, this case highlights the lack of medical follow-up and physician-guided return to activity after EHS.
Sarah Kölling, Rob Duffield, Daniel Erlacher, Ranel Venter and Shona L. Halson
summarize the role of sleep in athlete performance and recovery; particularly, factors affecting sleep behavior, the prevalence of sleep loss among athletes, and recommendations for intervention strategies. Definition and Measurement of Sleep The sleep–wake continuum is regulated by the interaction of
Haresh T. Suppiah, Chee Yong Low, Gabriel Choong and Michael Chia
adolescents sleeping significantly later, and less than their counterparts from North America and Europe. 5 The effects of sleep loss are shown to result in impaired metabolism, health, academic, and psychological outcomes. 6 , 7 Apart from adolescents, high-level athletes are recognized to experience
Sigridur L. Gudmundsdottir
than the shift observed in nonathlete adolescents and is mainly explained by the shift from weekdays to weekends ( 40 ). The mechanical pathway of how disrupted sleep may affect athletes’ functioning is not clear. One of the suggested physiological effects of sleep loss on athletic performance is via
Andressa Silva, Fernanda V. Narciso, Igor Soalheiro, Fernanda Viegas, Luísa S.N. Freitas, Adriano Lima, Bruno A. Leite, Haroldo C. Aleixo, Rob Duffield and Marco T. de Mello
.1080/02640414.2016.1184300 27173843 5. Fullagar HHK , Skorski S , Duffield R , Hammes D , Coutts AJ , Meyer T . Sleep and athletic performance: the effects of sleep loss on exercise performance, and physiological and cognitive responses to exercise . Sports Med . 2014 ; 45 ( 2 ): 161 – 186 . doi: 10.1007/s40279
Heidi R. Thornton, Jace A. Delaney, Grant M. Duthie and Ben J. Dascombe
, 5 , 6 with further evidence suggesting that sleep loss (deprivation and restriction) has profound detrimental effects on athletes’ exercise performance and physiological and cognitive capacities. 2 Investigating how the extensive training demands of team-sport athletes may compromise sleep may