Effect of two types of partial sleep deprivation on Taekwondo players’ performance during intermittent exercise

Sleep and Sport Performance

SUMMARY

Elite athletes and coaches believe sleep is the most important recovery strategy and widely consider it critical to optimal performance. Despite this perceived importance, there are numerous circumstances that can reduce sleep quantity and quality in athletic populations. Because of the effects of sleep loss on various physical, neurophysiological, and cognitive parameters, such perturbations can have consequences for performance and recovery outcomes. Although peer-reviewed literature examining the interaction between sleep, performance, and recovery in athletes is increasing, understanding of these issues remains equivocal. Perhaps most pertinently, the effect of sleep on sport performance does not align with a one-size-fits-all approach and rather depends on numerous factors such as type of sport, scheduling, time of the season, and the intraindividual requirements for sleep. The relationship between brain plasticity and memory, which in turn can influence learning processes and long-term memory consolidation, suggests that sleep may play an important role in learning new skills and tactics for both elite and developing athletes. The aim of this special issue review was to analyze the evidence of sleep loss on sport performance and recovery, with a specific focus on elite athletes. An assessment of these sleep-compromising situations that elite athletes may face during a typical season and practical considerations for alleviating these issues is also provided to further the understanding for medical professionals, scientists, and applied sporting practitioners alike.

Effects of Acute Sleep Loss on Physical Performance: A Systematic and Meta-Analytical Review

BACKGROUND

Sleep loss may influence subsequent physical performance. Quantifying the impact of sleep loss on physical performance is critical for individuals involved in athletic pursuits.

DESIGN

Systematic review and meta-analysis.

SEARCH AND INCLUSION

Studies were identified via the Web of Science, Scopus, and PsycINFO online databases. Investigations measuring exercise performance under 'control' (i.e., normal sleep, > 6 h in any 24 h period) and 'intervention' (i.e., sleep loss, ≤ 6 h sleep in any 24 h period) conditions were included. Performance tasks were classified into different exercise categories (anaerobic power, speed/power endurance, high-intensity interval exercise (HIIE), strength, endurance, strength-endurance, and skill). Multi-level random-effects meta-analyses and meta-regression analyses were conducted, including subgroup analyses to explore the influence of sleep-loss protocol (e.g., deprivation, restriction, early [delayed sleep onset] and late restriction [earlier than normal waking]), time of day the exercise task was performed (AM vs. PM) and body limb strength (upper vs. lower body).

RESULTS

Overall, 227 outcome measures (anaerobic power: n = 58; speed/power endurance: n = 32; HIIE: n = 27; strength: n = 66; endurance: n = 22; strength-endurance: n = 9; skill: n = 13) derived from 69 publications were included. Results indicated a negative impact of sleep loss on the percentage change (%_Δ) in exercise performance (n = 959 [89%] male; mean %_Δ =  - 7.56%, 95% CI - 11.9 to - 3.13, p = 0.001, I² = 98.1%). Effects were significant for all exercise categories. Subgroup analyses indicated that the pattern of sleep loss (i.e., deprivation, early and late restriction) preceding exercise is an important factor, with consistent negative effects only observed with deprivation and late-restriction protocols. A significant positive relationship was observed between time awake prior to the exercise task and %_Δ in performance for both deprivation and late-restriction protocols (~ 0.4% decrease for every hour awake prior to exercise). The negative effects of sleep loss on different exercise tasks performed in the PM were consistent, while tasks performed in the AM were largely unaffected.

CONCLUSIONS

Sleep loss appears to have a negative impact on exercise performance. If sleep loss is anticipated and unavoidable, individuals should avoid situations that lead to experiencing deprivation or late restriction, and prioritise morning exercise in an effort to maintain performance.

Effects of High-Intensity Interval Exercise and Acute Partial Sleep Deprivation on Cardiac Autonomic Modulation

Sleep deprivation in healthy adults has been associated with disrupted autonomic nervous system function, which in turn has been linked to cardiovascular health. High-intensity interval exercise (HIIE) may affect both sleep and cardiac autonomic modulation. Purpose: To investigate the impact of acute partial sleep deprivation on autonomic cardiac regulation before and after an acute bout of HIIE and the length of time for the autonomic system to return to resting levels. Methods: Fifteen healthy males with body mass index (BMI) of 25.8 ± 2.7 kg·m^-2 and age 31 ± 5 y participated in a reference sleep (~9.5 hr) with no HIIE (RS), a reference sleep with HIIE (RSX), and an acute partial sleep deprivation (~3.5 hr) with HIIE (SDX). HIIE was performed in 3:2 intervals at 90% and 40% of VO₂ reserve. Autonomic regulation through HRV selected time and frequency domain indices were recorded the night before, the morning of the next day, 1 hr-, 2 hr-, 4hr-, and 6-hr post-exercise. Results: HIIE performed in a 3:2 W:R ratio decreased the HRV (p < .05) at 1-hr post exercise and it took up to 4 hr to return to baseline levels. Parasympathetic related HRV indices increased the morning of the next day for SDX (p < .05). Acute partial sleep deprivation and HIIE did not modify the HRV responses compared to reference sleep and HIIE. Conclusion: HRV disturbance typically seen in responses to an acute episode of HIIE is not influenced by acute partial sleep deprivation.

Benefits of Daytime Napping Opportunity on Physical and Cognitive Performances in Physically Active Participants: A Systematic Review

BACKGROUND

Evidence suggests that athletes often experience chronic sleep disturbance. Napping is widely recommended as a safe and non-invasive intervention to counteract the negative effects of partial sleep deprivation. However, systematic reviews on the benefits of napping have yet to be undertaken.

OBJECTIVE

(i) To evaluate the effectiveness of diurnal napping opportunities on athletes' physical and cognitive performance and (ii) to outline how aspects of the study design (i.e., nap duration, exercise protocol, participants' fitness level and previous sleep quantity) can influence the potential effects of napping through a systematic appraisal of the literature.

METHODS

This systematic review was conducted in accordance with the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. PubMed, Web of Science and SCOPUS databases were searched up to June 2020 for relevant studies investigating the effect of napping on physical and cognitive performances in physically active participants. Fourteen strong-quality and four moderate-quality (mean QualSyst score = 75.75 ± 5.7%) studies met our inclusion criteria and were included in the final sample (total participants: 158 physically active and 168 athletes).

RESULTS

Most studies (n = 15) confirmed the beneficial effects of napping and showed that diurnal napping improved short-term physical performance (n = 10), endurance performance (n = 3) and specific skills performance (n = 2). Two studies showed no significant napping effect and only one study showed reduced sprint performance following diurnal napping. Moreover, napping improved reaction time (n = 3), attention (n = 2) and short-term memory (n = 1) performances. Importantly, "replacement naps" improved both physical and cognitive performance regardless of the type of exercise. However, "prophylactic naps" improved only jump, strength, running repeated-sprint, attention and reaction time performances. In addition, this systematic review revealed that longer nap opportunities (i.e., 90 min) resulted in better improvement of physical and cognitive performance and lower induced fatigue.

CONCLUSIONS

A diurnal nap seems to be an advantageous intervention to enhance recovery process and counteract the negative effect of partial sleep deprivation on physical and cognitive performance. Particularly, to optimize physical performances of athletes experiencing chronic lack of sleep, findings from the included individual studies suggest 90 min as the optimal nap duration. Diurnal napping may be beneficial for athletes but this benefit should be viewed with caution due to the quality of the evidence, risk of bias and the limited evidence about napping interventions.

High-Intensity Interval Exercise Performance and Short-Term Metabolic Responses to Overnight-Fasted Acute-Partial Sleep Deprivation

People practicing high-intensity interval exercise (HIIE) fasted during the morning hours under a lack of sleep. Such a habit may jeopardize the health benefits related to HIIE and adequate sleep. Fifteen habitually good sleeper males (age 31.1 ± 5.3 SD year) completed on a treadmill two isocaloric (500 kcal) HIIE sessions (3:2 min work:rest) averaged at 70% VO2reserve after 9-9.5 h of reference sleep exercise (RSE) and after 3-3.5 h of acute-partial sleep deprivation exercise (SSE). Diet and sleep patterns were controlled both 1 week prior and 2 days leading up to RSE and SSE. HIIE related performance and substrate utilization data were obtained from the continuous analysis of respiratory gases. Data were analyzed using repeated measures ANOVA with the baseline maximum oxygen uptake (VO2max) and body fat percentage (BF%) as covariates at p < 0.05. No difference was observed in VO2max, time to complete the HIIE, VE, RER, CHO%, and FAT% utilization during the experimental conditions. Whether attaining an adequate amount of sleep or not, the fasted HIIE performance and metabolism were not affected. We propose to practice the fasted HIIE under adequate sleep to receive the pleiotropic beneficial effects of sleep to the human body.

Acute Sleep Restriction Affects Sport-Specific But Not Athletic Performance in Junior Tennis Players

PURPOSE

Little is known about the effect of sleep restriction (SR) on different domains of athletes' physical performance. Therefore, the aim of this randomized, counterbalanced, and crossover study was to evaluate the effect of acute SR on sport-specific technical and athletic performance in male junior tennis players.

METHODS

Tennis players (N = 12; age 15.4 ± 2.6 y) were randomly allocated to either a sleep-restriction condition (SR, n = 6), where they experienced acute sleep restriction the night before the test session (≤5 h of sleep), or to a control condition (CON, n = 6), where they followed their habitual sleep-wake routines. Testing procedures included 20 left and right serves, 15 forehand and backhand crosscourt shots, and a repeated-sprint-ability test (RSA). The accuracy of serves and shots was considered for further analysis. One week later, players of SR joined CON, and players of CON experienced SR, and all test procedures were repeated.

RESULTS

Significant decrease in the accuracy of right (-17.5%, P = .010, effect size [ES] = 1.0, moderate) and left serve (-14.1%, P = .014, ES = 1.2, large), crosscourt backhand (-23.9%, P = .003, ES ≥ 2.0, very large), and forehand shot (-15.6%, P = .014, ES = 1.1, moderate) were observed in SR compared to CON, while RSA was similar in both conditions.

CONCLUSION

Coaches and athletes at the team and individual level should be aware that 1 night of SR affects sport-specific but not athletic performance in tennis players.

Caffeine Use or Napping to Enhance Repeated Sprint Performance After Partial Sleep Deprivation: Why Not Both?

PURPOSE

To compare the effect of a 20-minute nap opportunity (N20), a moderate dose of caffeine (CAF; 5 mg·kg-1), or a moderate dose of caffeine before N20 (CAF+N) as possible countermeasures to the decreased performance and the partial sleep deprivation-induced muscle damage.

METHODS

Nine male, highly trained judokas were randomly assigned to either baseline normal sleep night, placebo, N20, CAF, or CAF+N. Test sessions included the running-based anaerobic sprint test, from which the maximum (Pmax), mean (Pmean), and minimum (Pmin) powers were calculated. Biomarkers of muscle, hepatic, and cardiac damage and of enzymatic and nonenzymatic antioxidants were measured at rest and after the exercise.

RESULTS

N20 increased Pmax compared with placebo (P < .01, d = 0.75). CAF+N increased Pmax (P < .001, d = 1.5; d = 0.94), Pmin (P < .001, d = 2.79; d = 2.6), and Pmean (P < .001, d = 1.93; d = 1.79) compared with placebo and CAF, respectively. Postexercise creatine kinase increased whenever caffeine was added, that is, after CAF (P < .001, d = 1.19) and CAF+N (P < .001, d = 1.36). Postexercise uric acid increased whenever participants napped, that is, after N20 (P < .001, d = 2.19) and CAF+N (P < .001, d = 2.50) and decreased after CAF (P < .001, d = 2.96).

CONCLUSION

Napping improved repeated-sprint performance and antioxidant defense after partial sleep deprivation. Contrarily, caffeine increased muscle damage without improving performance. For sleep-deprived athletes, caffeine before a short nap opportunity would be more beneficial for repeated sprint performance than each treatment alone.

Sleep quality and athletic performance according to chronotype

BACKGROUND

When studying the quality of sleep in relation to athletic performance, the athlete's chronotype and habitual time consider important factors. We aim to investigate the sleep quality and athletes' performance according to chronotype in elite athletes.

METHODS

Three hundred forty elite athletes (males = 261, females = 79) were recruited for the present study. All participants were screening for chronotype by the Korean versions of the Morningness - Eveningness Questionnaire (MEQ-K). The Pittsburgh Sleep Quality Index (PSQI) and Wingate Anaerobic Test (WAnT) were measurement after screening.

RESULTS

PSQI global score, PSQI sleep quality, PSQI sleep onset latency, PSQI sleep disturbance, and PSQI daytime dysfunction were significant differences among the groups. WAnT mean power (W), mean power (W/kg), peak power (W), and peak power (W/kg) were significant differences among the groups. A negative correlation coefficient was found between PSQI score and WAnT mean power (W) (r = - 0.256, p < 0.01), mean power (W/kg) (r = - 0.270, p < 0.01), peak power (W) (r = - 0.220, p < 0.01), and peak power (W/kg) (r = - 0.248, p < 0.01).

CONCLUSIONS

This study indicates that related poor sleep quality and late-type chronotype may reduce the athletes' performance in elite athletes. In addition, the sleep quality is much higher in the early-type chronotype than in the late-type chronotype. Moreover, it also the athletic performance was better in the early-type chronotype than in the late-type chronotype.

Improved Physical Performance and Decreased Muscular and Oxidative Damage With Postlunch Napping After Partial Sleep Deprivation in Athletes

PURPOSE

To investigate the effects of napping after partial sleep deprivation (PSD) on reaction time, mood, and biochemical response to repeated-sprint exercise in athletes.

METHODS

Nine male judokas performed 4 test sessions in a counterbalanced and randomized order. Participants accomplished 1 control session after a normal sleep night (NSN) and 3 after PSD with (1) no nap, (2) ∼20-min nap (N20), and (3) ∼90-min nap (N90) opportunities. Test sessions included the running-based anaerobic sprint test, reaction time, Hooper index, and Epworth Sleepiness Scale. Muscle-damage biomarkers and antioxidant status were evaluated before and after exercise.

RESULTS

PSD decreased maximum (P < .001, d = 1.12), mean (P < .001, d = 1.33), and minimum (P < .001, d = 1.15) powers compared with NSN. However, N20 and N90 enhanced maximum power compared with PSD (P < .05, d = 0.54; P < .001, d = 1.06, respectively). Minimum power and mean power increased only after N90 (P < .001, d = 1.63; P < .001, d = 1.16, respectively). Epworth Sleepiness Scale increased after PSD (P < .001, d = 0.86) and decreased after N20 (P < .001, d = 1.36) and N90 (P < .001, d = 2.07). N20 reduced multiple-choice reaction time (P < .001, d = 0.61). Despite performance decrement, PSD increased postexercise aspartate aminotransferase (P < .001, d = 4.16) and decreased glutathione peroxidase (P < .001, d = 4.02) compared with NSN. However, the highest performances after N90 were accompanied with lesser aspartate aminotransferase (P < .001, d = 1.74) and higher glutathione peroxidase (P < .001, d = 0.86) compared with PSD.

CONCLUSIONS

Napping could be preventive against performance degradation caused by sleep loss. A short nap opportunity could be more beneficial when the subsequent effort is brief and requires frequent decision making. However, a longer nap opportunity could be preventive against muscle and oxidative damage, even for higher performances.

Extended Sleep Maintains Endurance Performance Better than Normal or Restricted Sleep

PURPOSE

The cumulative influence of sleep time on endurance performance remains unclear. This study examined the effects of three consecutive nights of both sleep extension (SE) and sleep restriction (SR) on endurance cycling performance.

METHODS

Endurance cyclists/triathletes (n = 9) completed a counterbalanced crossover experiment with three conditions: SR, normal sleep (NS), and SE. Each condition comprised seven days/nights of data collection (-2, -1, D1, D2, D3, D4, and +1). Sleep was monitored using actigraphy throughout. Participants completed testing sessions on days D1-D4 that included an endurance time-trial (TT), mood, and psychomotor vigilance assessment. Perceived exertion (RPE) was monitored throughout each TT. Participants slept habitually before D1; however, time in bed was reduced by 30% (SR), remained normal (NS), or extended by 30% (SE) on nights D1, D2, and D3. Data were analyzed using generalized estimating equations.

RESULTS

On nights D1, D2, and D3, total sleep time was longer (P < 0.001) in the SE condition (8.6 ± 1.0, 8.3 ± 0.6, and 8.2 ± 0.6 h, respectively) and shorter (P < 0.001) in the SR condition (4.7 ± 0.8, 4.8 ± 0.8, and 4.9 ± 0.4 h) compared with NS (7.1 ± 0.8, 6.5 ± 1.0, and 6.9 ± 0.7 h). Compared with NS, TT performance was slower (P < 0.02) on D3 of SR (58.8 ± 2.5 vs 60.4 ± 3.7 min) and faster (P < 0.02) on D4 of SE (58.7 ± 3.4 vs 56.8 ± 3.1 min). RPE was not different between or within conditions. Compared with NS, mood disturbance was higher, and psychomotor vigilance impaired, after SR. Compared with NS, psychomotor vigilance improved after SE.

CONCLUSION

Sleep extension for three nights led to better maintenance of endurance performance compared with normal and restricted sleep. Sleep restriction impaired performance. Cumulative sleep time affects performance by altering the perceived exertion of a given exercise intensity. Endurance athletes should sleep >8 h per night to optimize performance.

Does one night of partial sleep deprivation affect the evening performance during intermittent exercise in Taekwondo players?

Athletes and coaches believe that adequate sleep is essential for peak performance. There is ample scientific evidence which support the conclusion that sleep loss seems to stress many physiological functions in humans. The aim of this study was to determine the effect of one night’s sleep deprivation on intermittent exercise performance in the evening of the following day. Ten male Taekwondo players performed the Yo-Yo intermittent recovery test (YYIRT) in three sleep conditions (reference sleep night [RN], partial sleep deprivation at the beginning of night [PSDBN], partial sleep deprivation at the end of night [PSDEN]) in a counterbalanced order, allowing a recovery period ≥36 hr in between them. Heart rate peak (HRpeak), plasma lactate concentrations (Lac) and rating of perceived exertion (RPE) were measured during the test. A significant effect of sleep restriction was observed on the total distance covered in YYIRT (P<0.0005) and Lac (P<0.01) in comparison with the RN. In addition, performance more decreased after PSDEN (P<0.0005) than PSDBN (P<0.05). Also, Lac decreased significantly only after PS-DEN (P<0.05) compared with RN. However, there were no significant changes in HRpeak and RPE after the two types of partial sleep deprivation compared to RN. The present study indicates that short-term sleep restriction affect the intermittent performance, as well as the Lac levels of the Taekwondo players in the evening of the following day, without alteration of HRpeak and RPE.

Sleep and athletic performance: the effects of sleep loss on exercise performance, and physiological and cognitive responses to exercise

Although its true function remains unclear, sleep is considered critical to human physiological and cognitive function. Equally, since sleep loss is a common occurrence prior to competition in athletes, this could significantly impact upon their athletic performance. Much of the previous research has reported that exercise performance is negatively affected following sleep loss; however, conflicting findings mean that the extent, influence, and mechanisms of sleep loss affecting exercise performance remain uncertain. For instance, research indicates some maximal physical efforts and gross motor performances can be maintained. In comparison, the few published studies investigating the effect of sleep loss on performance in athletes report a reduction in sport-specific performance. The effects of sleep loss on physiological responses to exercise also remain equivocal; however, it appears a reduction in sleep quality and quantity could result in an autonomic nervous system imbalance, simulating symptoms of the overtraining syndrome. Additionally, increases in pro-inflammatory cytokines following sleep loss could promote immune system dysfunction. Of further concern, numerous studies investigating the effects of sleep loss on cognitive function report slower and less accurate cognitive performance. Based on this context, this review aims to evaluate the importance and prevalence of sleep in athletes and summarises the effects of sleep loss (restriction and deprivation) on exercise performance, and physiological and cognitive responses to exercise. Given the equivocal understanding of sleep and athletic performance outcomes, further research and consideration is required to obtain a greater knowledge of the interaction between sleep and performance.