No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
The effect of partial sleep deprivation on weight-lifting performance
Abstract
This study examined the effects of partial sleep deprivation on submaximal and maximal weight-lifting tasks and on subjective states pre- and post-activity. Eight male subjects (aged 18-24 years) were restricted to a nightly ration of 3 h sleep for 3 successive nights after baseline measures on the first day. A 4 day period where normal sleep was permitted fulfilled a control condition, the normal and sleep-deprived conditions being counterbalanced and separated by 10 days. The weight-lifting tasks consisted of biceps curl, bench press, leg press, and dead lift. For each exercise a submaximal load, corresponding to a fixed value on a category ratio scale of exertion, was determined for 20 repetitions; the maximal lift for that exercise was then obtained. A profile of mood states and subjective sleepiness were determined at each test occasion, tests being conducted in the evening of each day. There was no significant effect of sleep loss on performance of maximal biceps curl (p < 0.05) but a significant effect was noted on maximal bench press, leg press, and dead lift (p < 0.001). Trend analysis indicated decreased performance in submaximal lifts for all the 4 tasks: the deterioration was significant after the second night of sleep loss (p < 0.01). Performing the lifts had little influence on sleepiness ratings which increased linearly with successive days of sleep loss. Mood states of confusion, vigour, and fatigue were affected significantly by the sleep deprivation regimen (p < 0.001), but there was no significant effect of sleep loss or anger, tension, and depression (p > 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
... O sono usualmente cumpre uma função de restituição fisiológica no organismo e tem sido considerado um importante fator para o desempenho de atletas (AKERSTEDT; NILSSON, 2003;REARDON et al., 2019), visto que muitos atletas, amadores ou de elite, são maus dormidores e dormem menos do que o suficiente (CARTER et al., 2020;DREW et al., 2018;PEIFFER, 2015;ROBERTS;TEO;WARMINGTON, 2019). Ademais, a PS e a PPS, que diferem entre si no tempo total de PS, usualmente provocam alterações de humor que podem cooperar para prejuízos de desempenho (ANGUS; HESLEGRAVE; MYLES, 1985;BOONSTRA et al., 2007;EDWARDS;WATERHOUSE, 2009;MENEY et al., 1998;REILLY;PIERCY, 1994;SKEIN et al., 2011). ...
... A literatura científica especializada mostra que a PPS promove prejuízos ao desempenho físico e percepto-cognitivo, às respostas fisiológicas ao exercício físico e ao desempenho específico de algumas modalidades esportivas (ABEDELMALEK et al., 2013;AXELSSON et al., 2008;EDWARDS;WATERHOUSE, 2009;LÉGER et al., 2008;MOUGIN et al., 1991MOUGIN et al., , 2001OTMANI et al., 2005;REILLY;PIERCY, 1994;REYNER;HORNE, 2013;SOUISSI et al., 2013;VGONTZAS et al., 2004). Apesar disso, os resultados, que ainda são conflitantes (FULLAGAR et al., 2015(FULLAGAR et al., , 2019VAN CUTSEM et al., 2017b), são incipientes em apontar os mecanismos pelos quais a PPS compromete o desempenho. ...
... Dito isto, apesar do caráter pouco ecológico de alguns procedimentos metodológicos adotados, estudos têm demonstrado prejuízos da PS (AZBOY; KAYGISIZ, 2009;FRÖBERG et al., 1975;PALLESEN et al., 2017;SKEIN et al., 2011SKEIN et al., , 2013SOUISSI et al., 2003;SYMONS;MYLES, 1988;TAKEUCHI et al., 1985) e da PPS (ABEDELMALEK et al., 2013;AXELSSON et al., 2008;EDWARDS;WATERHOUSE, 2009;JARRAYA et al., 2014;LÉGER et al., 2008;MOUGIN et al., 1991MOUGIN et al., , 2001OTMANI et al., 2005;REILLY;PIERCY, 1994;REYNER;HORNE, 2013;SOUISSI et al., 2013;VGONTZAS et al., 2004) no desempenho físico e comportamental de atletas. ...
A fadiga mental (FM) e a privação/privação parcial do sono (PS/PPS), por si só, prejudicam o desempenho percepto-cognitivo e físico de atletas das mais variadas modalidades esportivas. Estudos que avaliem os efeitos da FM e PPS conjugados, que individualizem a carga cognitiva e a duração da PPS e que analisem o desempenho percepto-cognitivo e físico de atletas de voleibol de praia a partir de testes ecológicos são necessários. Esse estudo teve como objetivo analisar os efeitos da PPS e da FM, conjugadas e isoladas, no desempenho percepto-cognitivo e físico em atletas treinados de voleibol de praia. Participaram do estudo 14 atletas treinados de voleibol de praia (12 homens; 17,6±1,5 anos). O estudo foi do tipo experimental de medidas repetidas, cruzado e randomizado e adotou quatro condições experimentais: a) Controle (CT), b) FM, c) PPS e d) PPS+FM. A FM foi induzida pelo Stroop task incongruente e a atividade de sono dos voluntários foi monitorada por oito noites consecutivas. A carga cognitiva e a duração da PPS foram individualizadas. O cumprimento da PPS foi monitorado por formulário online, preenchido em intervalos de 15 minutos pelo tempo que perdurou a PPS. O desempenho físico foi medido por uma série de 50 saltos com contramovimento com intervalos de 5 segundos entre cada salto realizados em esforço máximo e o desempenho percepto-cognitivo foi avaliado via testes visuomotores com luzes de light emitting diode (LED) que simularam ações de defesa e bloqueio no voleibol de praia. Os desfechos primários do estudo foram analisados pela análise de variância ANOVA de um fator (condição [4]) e o post-hoc de bonferroni foi aplicado para localizar as eventuais diferenças estatisticamente significantes. Os dados contínuos estão apresentados como média e desvio padrão e os categóricos como valores absolutos e relativos. A condição PPS causou respostas mais lentas no tempo de reação (TR) “mais rápido” (p=0,02; d de Cohen=1,12; PPS: 1562.14±109.06 ms vs CT: 1440.71±101.41 ms) e “média” (p=0,02; d de Cohen=1,13; PPS: 1874.29±144.63 ms vs CT: 1727.14±113.30 ms) do teste visuomotor de defesa comparado ao CT e a condição PPS+FM apresentou prejuízo no TR “média” (p<0,01; d de Cohen=1,38; PPS+FM: 1906.43±133.45 ms vs CT: 1727.14±113.30 ms) do mesmo teste comparado ao CT. Para o teste visuomotor de bloqueio foi observado que a condição PPS+FM prejudicou o TR “média” (p=0,04; d de Cohen=1,06; PPS+FM: 722.14±100.09 ms vs CT: 631.42±82.17 ms) e “índice de desempenho” (p=0,02; d de Cohen=1,18; PPS+FM: 0,14±0,02 u.a vs CT: 0,16±0,02 u.a) comparado ao CT. O desempenho físico não foi prejudicado por nenhuma condição experimental. Conclui-se, portanto, que a PPS, isolada e conjugada à FM, prejudicam o desempenho percepto-cognitivo de atletas treinados de voleibol de praia, entretanto, os prejuízos da PPS conjugados à FM não se sobrepõem àqueles observados na PPS quando isolada. Adicionalmente, o desempenho físico não foi prejudicado nem pela FM nem pela PPS em atletas treinados de voleibol de praia.
... The consequences of sleep loss (e.g., altered training adaptations, increased workplace accidents [38,39]) are likely to have multiple aetiologies. Negative consequences may result from a decrease in muscular strength [40] and/or endurance [41], change in mood (e.g., decreased motivation) [42], an increase in perceived effort [43,44], changes to cognitive processing ability (e.g., decision making, executive function) and/or a reduction in fine motor skills [45], or a combination of these factors. ...
... Some studies included in this meta-analysis assessed the influence of sleep loss on more than one performance task, either belonging to the same category [40,41,53,58,59,63,64,[75][76][77][78][79][80][81][82][83][84], or different categories [41, 43, 44, 56-59, 61, 62, 64, 65, 75, 77-81, 85-102]. For example, Souissi et al. [78] measured anaerobic power in two separate tasks (i.e., squat jump and Wingate test). ...
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.
... Therefore, sleep disturbance causes weight gain [1,2], hastening the onset of diseases and endangering mental health [3], which further results in secondary problems such as lack of concentration and poor academic performance. In athletes, sleep is considered to play an essential role in physical and psychological recovery [4], and inadequate sleep has been associated with muscle weakness [5], increased heart rate, ventilation, lactate production [6], and subjective exercise intensity [5] at specific exercise intensities. Furthermore, numerous previous studies have demonstrated the importance of sleep in health and performance [7,8]. ...
... Therefore, sleep disturbance causes weight gain [1,2], hastening the onset of diseases and endangering mental health [3], which further results in secondary problems such as lack of concentration and poor academic performance. In athletes, sleep is considered to play an essential role in physical and psychological recovery [4], and inadequate sleep has been associated with muscle weakness [5], increased heart rate, ventilation, lactate production [6], and subjective exercise intensity [5] at specific exercise intensities. Furthermore, numerous previous studies have demonstrated the importance of sleep in health and performance [7,8]. ...
Objectives:
This study aimed to characterize the sleep quality and nutrient intake of Japanese female college athletes to provide specific conditioning support.
Methods:
A cross-sectional survey conducted between December 2019 and January 2020 during the regular training season in Niigata City, located at 139°02' E longitude and 37°55' N latitude. Overall, 120 female university student-athletes from eight clubs were selected. All sports were at the national level of competition. The Pittsburgh Sleep Quality Index (PSQI) assessed sleep quality. Nutrient intake was assessed using Excel nutrition software through the Food Intake Frequency Questionnaire.
Results:
The mean PSQI score was 4.5 ± 2.5, with 29% of participants having a PSQI score ≥ 5.5. The sleep duration was 6.8 ± 1.1 h, with 45% of participants sleeping <7 h. The energy intake was 1800 ± 419 kcal, with no correlation between PSQI score and nutrient intake.
Conclusions:
PSQI scores were higher compared with other studies, but many participants had shorter sleep duration and lower nutrient intake, these data suggest that there is the possibility of improving the habits of Japanese athletes by increasing the subjects' amount of sleep time and food intake.
... The last component that we will review and suggest as a potential modifier of maximal isometric strength over time of day is the potential for the muscle circadian clock to effect intrinsic muscle properties that modulate strength. Increasingly, data in both humans and mice suggest that systemic or muscle-specific disruption of the circadian clock results in a reduction of maximal isometric muscle strength (5,24,51,77,83,105). Studies in humans have shown that disruption of the circadian clock mechanism by sleep disruption or sleep deprivation using protocols of 36 h or more of interrupted sleep have been shown to significantly reduce maximal isometric strength by 17% (51,77,105). ...
... Increasingly, data in both humans and mice suggest that systemic or muscle-specific disruption of the circadian clock results in a reduction of maximal isometric muscle strength (5,24,51,77,83,105). Studies in humans have shown that disruption of the circadian clock mechanism by sleep disruption or sleep deprivation using protocols of 36 h or more of interrupted sleep have been shown to significantly reduce maximal isometric strength by 17% (51,77,105). We note that among these studies, Vaara et al. (105) report no significant differences among EMG measures during maximal isometric contractions after sleep deprivation, yet additional studies are needed to fully characterize the effect of sleep deprivation on central motivation and its downstream consequences on isometric strength. ...
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.
... La desventaja de este estudio es que se utilizó un diseño pre-experimental de un solo intento, lo que se conoce como grupos independientes, controlando muy pocas variables (Thomas y Nelson, 2007). Aun así, no se hallaron otros estudios que encuentren diferencias en el rendimiento físico con una noche de privación de sueño (Reilly & Piercy, 1994;Taheri & Arabemeri, 2012). ...
... En este estudio se encontró que una noche de privación de sueño no es un factor que influya en el rendimiento físico de una prueba realizada el día siguiente. Sin embargo, de acuerdo a la evidencia científica encontrada, el rendimiento físico comienza a decrecer después de 30 horas de estar despierto (Oliver, Costa, Laing, Bilzon & Walsh, 2009;Reilly & Piercy, 1994;Souissi, et al., 2013;Souissi, Sesboue, Gauthier, Larue & Davenne 2003). ...
El objetivo de este estudio fue determinar si la resistencia aeróbica y la concentración de lactato en sangre, pueden ser influenciados por la privación parcial o total del sueño en un grupo de deportistas. Se reclutaron 13 deportistas masculinos (21.8 ± 2.9 años de edad) los cuales fueron sometidos a tres condiciones experimentales: dormir cuatro horas (D4H), no dormir (0H) y una condición contol de dormir ocho horas (D8H). No se encontraron diferencias estadísticamente significativas en la resistencia aeróbica (p=.845). De la misma manera, no se halló diferencia significativa en la concentración de lactato en sangre (p>.05). Estos resultados señalan que la privación parcial (dormir cuatro horas) o total (no dormir) del sueño, previo a una prueba física, no es un factor que influya en el rendimiento aeróbico ni en la concentración de lactato en sangre en comparación a la cantidad de horas de sueño recomendadas (dormir ocho horas).Abstract. The purpose of this study was to determinate if aerobic performance and blood lactate concentration are influenced by partial or total sleep deprivation. Thirteen male athletes (age: 21.8 ± 2.9 y.o) were randomly assigned to three experimental conditions: sleep four hours (D4H), no sleep (0H), and sleep eigth hours (D8H, control group). No significant difference was found in the aerobic performance (p=.845). Similarly, there was no sifnificant difference in blood lactate concentration (p>.05). This results suggest that partial (sleep four hours) or total (no sleep) sleep deprivation before a physical test are not a factor influencing aerobic performance or blood lactate concentration compared to the amount of recommended hours of sleep (sleep eight hours).
... Although it is not fully understood, additional factors such as sleep (i.e., quality and quantity), stress hormones (e.g., cortisol), androgenic hormones (e.g., testosterone), and metabolic rate may influence changes in body composition (38, 46,53,71). Unfortunately, many training and nutrition studies do not take into account these important covariates. However, when examining the body of literature that has investigated the effects of these factors on body composition, it is clear they can impact how each individual is responding to the interventions. ...
... Additional data investigating sleep deprivation have demonstrated negative effects on multiple athletic performance variables and recovery capabilities (17,41,53). For example, Reilly and Piercy (53) observed significant reductions in strength-endurance performance and total volume load on compound exercises such as the bench press, deadlift, and leg press when subjects were in a sleep-restricted state. ...
Despite the lack of standardized terminology, building muscle and losing fat concomitantly has been referred to as body recomposition by practitioners. Although many suggest that this only occurs in untrained/novice and overweight/obese populations, there is a substantial amount of literature demonstrating this body recomposition phenomenon in resistance-trained individuals. Moreover, 2 key factors influencing these adaptations are progressive resistance training coupled with evidence-based nutritional strategies. This review examines some of the current literature demonstrating body recomposition in various trained populations, the aforementioned key factors, nontraining/nutrition variables (i.e., sleep, hormones), and potential limitations due to body composition assessments. In addition, this review points out the areas where more research is warranted.
... By contrast, 1-2 days of total sleep deprivation or 10 days of PSD has been shown to increase hs-CRP level (Meier-Ewert et al., 2004). Moreover, 3 consecutive days of PSD (sleep deprivation of 3 hr per night) has been shown to reduce maximal muscular strength during bench press, leg press, and deadlift exercises (Reilly & Piercy, 1994). Considering our trials lasted for a single night, it is possible that the severity of sleep deprivation (total sleep deprivation or PSD) or length of sleep loss (a single night of PSD or consecutive days of PSD) may have affected the present outcomes, and future research in long trials (3-7 days) may be warranted. ...
... Secondly, because we manipulated sleep duration during a single night, the cumulative effects of PSD during a training period remain unclear. Some previous studies that have used consecutive days of PSD have presented attenuated muscle function (Reilly & Piercy, 1994) and endurance capacity (Roberts, Teo, Aisbett, & Warmington, 2019), however, their findings are not fully consistent (Spencer, Bishop, Dawson, & Goodman, 2005). Thirdly, the present study shortened sleep duration by 60% during the early phase of the night. ...
The purpose of the present study was to determine the effects of partial sleep deprivation (PSD) after an exercise session in the evening on the endurance exercise-induced hepcidin response the following morning. Ten recreationally trained males participated under two different conditions. Each condition consisted of 2 consecutive days of training (days 1 and 2). On day 1, participants ran for 60 min at 75% of maximal oxygen uptake (
V
˙
O2max ) followed by 100 drop jumps. Sleep duration at night was manipulated, with a normal length of sleep (CON condition, 23:00-07:00 hr) or a shortened length of sleep (PSD condition). On the morning of day 2, the participants ran for 60 min at 65% of
V
˙
O2max . Sleep duration was significantly shorter under the PSD condition (141.2 ± 13.3 min) than under the CON condition (469.0 ± 2.3 min, p < .0001). Serum hepcidin, plasma interleukin (IL)-6, serum haptoglobin, iron, and myoglobin levels did not differ significantly between the conditions (p > .05) on the morning (before exercise) of day 2. Additionally, the 3-hr postexercise levels for the hematological variables were not significantly different between the two conditions (p > .05). In conclusion, the present study demonstrated that a single night of PSD after an exercise session in the evening did not affect baseline serum hepcidin level the following morning. Moreover, a 60 min run the following morning increased serum hepcidin and plasma IL-6 levels significantly, but the exercise-induced elevations were not affected by PSD.
... Therefore, during these four weeks of fasting, athletes face acute shortages of food and fluids, sleep deprivation (11)(12)(13) and more changes in psychological and social behaviours that alter the rhythmic pattern of many biological variables (14)(15)(16). Thus, it can negatively affect physical performance (17)(18)(19). ...
Background:
Ramadan observance has been practiced by many faith groups and cultures worldwide. Mo-reover, recently, it has been adopted as a natural alternative to promote public health. During Ramadan, our circadian rhythm can be altered. This study investigates how athletes' chronotype and sleep patterns impact aerobic fitness during Ramadan intermittent fasting.
Study design:
A prospective cohort design with repeated measurements was adopted. We measured the chronotype, maximal Oxygen Uptake as a measure of aerobic performance, and sleep patterns before and during Ramadan intermittent fasting. Then we explored the correlation among these variables.
Methods:
50 amateur athletes (Mean age = 17.22 years SD = 1.15) from Morocco participated in this study. The maximal Oxygen Uptake was measured with the 20-m shuttle-run test. The chronotype was assessed by the Morningness-Eveningness Questionnaire. The sleep timing was assessed by Sleep Timing Question-naire. We also assessed sleep quality with the Pittsburgh Sleep Quality Index. We examined the difference between variable means before and during Ramadan, also considering chronotype and sleep patterns of participants.
Results:
The results showed a significant decrease in sleep quality and maximal Oxygen Uptake during the Ramadan Intermittent Fasting. Also, we found a significant correlation between the chronotype, time in bed and time spent asleep. However, chronotype and sleep quality did not affect maximal Oxygen Uptake during the Ramadan intermittent fasting.
Conclusions:
Sleep and chronotype do not influence physical performance during Ramadan Intermittent Fasting. More research is needed to identify the leading cause of the drop in aerobic performance.
... However, Reilly and Deykin (1983) partially restricted sleep for three consecutive nights (2.5 h per night) and reported effects on psychomotor function on the first night, with hand grip strength being affected on the third night. This suggests that when partial sleep loss is employed over multiple nights, impairments on weightlifting performance are more pronounced on the second and third day of sleep loss; suggesting tasks that require greater activation and of larger muscle groups, are more susceptible to sleep loss (Bambaeichi et al. 2005;Reilly and Piercy 1994;Thun et al. 2015). Gross muscular tasks that require less "time on task" are least affected by partial sleep restriction, due to the temporary effort required; in contrast extended tasks or those of a repetitive nature such as Wingate's or sprints are affected to a greater degree (Brotherton et al. 2019;Waterhouse et al. 2007). ...
We have investigated the effects that partial-sleep-restriction (PSR0, 4-h sleep retiring at 02:30 and waking at 06:30 h for two consecutive nights) have on 07:30 and 17:00 h cognitive and submaximal weightlifting; and whether this performance improves at 17:00 h following a 13:00 h powernap (0, 30 or 60-min). Fifteen resistance-trained males participated in this study. Prior to the experimental protocol, one repetition max (1RM) bench press and back squat, normative habitual sleep and food intake were recorded. Participants were familiarised with the testing protocol, then completed three experimental conditions: (i) PSR with no nap (PSR0); (ii) PSR with a 30-min nap (PSR30) and (iii) PSR with a 60-min nap (PSR60). Conditions were separated by 7 days with trial order counterbalanced. Intra-aural temperature, Profile of Mood Scores, word-colour interference, alertness and tiredness values were measured at 07:30, 11:00, 14:00, 17:00 h on the day of exercise protocol. Following final temperature measurements at 07:30 h and 17:00 h, participants completed a 5-min active warm-up before performing three repetitions of left and right-hand grip strength, followed by three repetitions at each incremental load (40, 60 and 80% of 1RM) for bench press and back squat, with a 5-min recovery between each repetition. A linear encoder was attached perpendicular to the bar used for the exercises. Average power (AP), average velocity (AV), peak velocity (PV), displacement (D) and time-to-peak velocity (tPV) were measured (MuscleLab software) during the concentric phase of the movements. Data were analysed using general linear models with repeated measures. The main findings were that implementing a nap at 13:00 h had no effect on measures of strength (grip, bench press or back squat). There was a main effect for time of day with greatest performance at 17:00 h for measures of strength. In addition to a significant effect for "load" on the bar for bench press and back squat where AP, AV, PV, D values were greatest at 40% (P < 0.05) and decreased with increased load, whereas tPV and RPE values increased with load; despite this no interaction of "load and condition" were present. A post lunch nap of 30- and 60-minute durations improved mood state, with feelings of alertness, vigour and happiness highest at 17:00 h, in contrast to confusion, tiredness and fatigue (P < 0.05), which were greater in the morning (07:30 h). The word-colour interference test, used as an indicator of cognitive function, reported significant main effect for condition, with the highest total test score in PSR60 condition (P = 0.015). In summary, unlike strength measures the implementation of a 30 or 60-minute nap improved cognitive function when in a partially sleep restricted state, compared to no nap.
... Nonetheless, studies have consistently established that sleep disturbances are more frequent among women than men. Specifically, females are 1.3 to 1.8 times more likely to report sleeping problems (e.g., interrupted and inadequate sleep, lower sleep quality, and struggling to fall and stay asleep) [28][29][30]. In turn, these problems may negatively impact performance (e.g., in relation to strength) [31], enhance perceived effort, provoke changes in mood (e.g., decreased motivation) [32], induce changes in cognitive processing ability (e.g., executive function), and/or precipitate a decline in motor skills [33]. ...
This study aimed to examine female recreational (FRC) athletes' knowledge of the menstrual cycle and their perception of how each phase affects their performance, mood, and sleep. One hundred and sixty-four (n = 164) FRC athletes completed an online survey. The questionnaire employed was based on previously validated questionnaires and consisted of three different sections: (a) knowledge about the menstrual cycle, (b) menstrual cycle symptoms, and (c) menstrual cycle and performance. The results indicated that 70.1% of the surveyed FRC athletes were not knowledgeable regarding the phases of the menstrual cycle, with 55.5% being ignorant of the specific hormones released during the cycle. Furthermore, 37.8% perceived that their performance was sometimes affected during the early follicular phase, with the main symptoms being physical fatigue (17.9%) and a more irritable mood (25.9%). In addition, 19.5% of the FRC athletes reported sleeping disturbances, and 20.4% described changes in sleep quality during menstruation. Lastly, 11.9% of the FRC athletes reported suffering from a combination of mood swings, sleeping problems, bloating or stomach issues, breast tenderness, headaches, and fatigue prior to menstruation. The results of this study provide valuable insights into how FRC athletes experience the menstrual cycle, which can help RC athletes and trainers better understand their needs and support them in achieving optimal performance.
... Regarding relative sleep deprivation, missing the first few hours of the night doesn't seem to affect performance [201,203,204]. However, partial sleep deprivation over multiple days has been shown to have the opposite effect, probably because it increases perceived effort, sleepiness, and weariness [205]. ...
Objectives
This study was a narrative review of the importance of circadian rhythm (CR), describes the underlying mechanisms of CR in sports performance, emphasizes the reciprocal link between CR, endocrine homeostasis and sex differences, and the unique role of the circadian clock in immune system function and coordination.
Method
As a narrative review study, a comprehensive search was conducted in PubMed, Scopus, and Web of Science (core collection) databases using the keywords “circadian rhythm”, “sports performance”, “hormonal regulation”, “immune system”, and “injury prevention”. Inclusion criteria were studies published in English and peer-reviewed journals until July 2023. Studies that examined the role of CR in sports performance, hormonal status, immune system function, and injury prevention in athletes were selected for review.
Results
CR is followed by almost all physiological and biochemical activities in the human body. In humans, the superchiasmatic nucleus controls many daily biorhythms under solar time, including the sleep-wake cycle. A body of literature indicates that the peak performance of essential indicators of sports performance is primarily in the afternoon hours, and the evening of actions occurs roughly at the peak of core body temperature. Recent studies have demonstrated that the time of day that exercise is performed affects the achievement of good physical performance. This review also shows various biomarkers of cellular damage in weariness and the underlying mechanisms of diurnal fluctuations. According to the clock, CR can be synchronized with photonic and non-photonic stimuli (i.e., temperature, physical activity, and food intake), and feeding patterns and diet changes can affect CR and redox markers. It also emphasizes the reciprocal links between CR and endocrine homeostasis, the specific role of the circadian clock in coordinating immune system function, and the relationship between circadian clocks and sex differences.
Conclusion
The interaction between insufficient sleep and time of day on performance has been established in this study because it is crucial to balance training, recovery, and sleep duration to attain optimal sports performance.
... Sleep is a critical component of optimal physiological function and physical recovery. Sleep deprivation and chronic poor sleep have been shown to negatively impact cognitive functioning [39], learning and memory [40], metabolism and endocrine function [41], and physical performance [42,43]. Reserve Officers' Training Corps cadets are often required to wake up in the early morning for daily physical training, followed by their typical school courses and extracurricular activities. ...
The purpose of this study was to assess the dietary habits, prevalence of low energy availability (EA), and sleep quality in a cohort of male army Reserve Officer Training Corps (ROTC) cadets, and to investigate the relationship between EA and sleep quality as well as EA and various body composition variables that are important for tactical readiness. Thirteen male army ROTC cadets (22.2 ± 4.1 yrs; BMI: 26.1 ± 2.3) had their EA and body composition assessed using diet and exercise records alongside bioelectrical impedance analysis. Cadets also completed a validated sleep questionnaire. Sixty-two percent of participants presented with clinically low EA (<30 kcal/kg fat-free mass [FFM]) and none met the optimum EA threshold (≥45 kcals/kg FFM). Dietary analysis indicated that 15%, 23%, 46%, 23%, and 7% of cadets met the Military Dietary Reference Intakes (MDRI) for calories, carbohydrates, protein, fat, and fiber, respectively. Additionally, 85% of cadets exhibited poor sleep quality. Significant associations between EA and fat mass/percent body fat were shown (p < 0.05). There was, however, no statistically significant correlation between EA and sleep quality. The present study found a high prevalence of low EA and sleep disturbance among male army ROTC cadets and that many were unable to meet the MDRIs for energy and macronutrient intake. Further, low EA was associated with higher percent body fat and fat mass but not sleep quality.
... High fatigue levels might be related to disturbances in sleep (Fullagar et al. 2016), and studies in partial sleep deprivation conducted with athletes reported increased fatigue, increased errors, reduced maximal power, and impaired decision-making (Reilly and Edwards 2007). Even though athletes might be able to overcome the adverse effects of sleep loss in single all-out efforts (Reilly and Edwards 2007), this might not be the case in prolonged training sessions and competitions (Reilly and Piercy 1994;Reilly and Edwards 2007). Studies conducted with clinical populations have also found that disrupted sleep is linked with greater fatigue and poorer health (Lorton et al. 2006). ...
The current study aimed to describe sleep habits and analyze the associations between sleep indices, changes in perceived fatigue (Δ Fatigue) and external training load measures in women soccer players during a 7-day training camp. Sixteen elite women soccer players (age: 25.4 ± 3.6 years; mean ± SD) from the Portuguese Women’s National Team participated in the study. Sleep indices (sleep duration and efficiency) were measured using a wrist-worn accelerometer. External training loads measures were measured using GPS devices. Players also reported perceived fatigue using a Likert scale (1 - very, very low to 7 – very, very high) before and immediately after sleep. Players' within- subject coefficient of variation for sleep duration was 5.6%, and 4.6% for sleep efficiency. Individually, 8 players (50%) slept less than 7 h per night throughout the training camp, and the same number of athletes had a sleep efficiency lower than 85%. Similar values (p<0.05) were measured for sleep duration and efficiency between training and match days. A moderate negative within-subjects correlation was found between Δ Fatigue and sleep duration (adjusted for pre-sleep fatigue) [r = -0.32; 95% Confidence Interval (-0.51 – -0.08); p = 0.04]. These findings reinforce the importance of sleep in the recovery process of elite women soccer players, showing that more sleep may help to attenuate fatigue.
... 23 Further, sleep duration and quality during season were found to have an impact on athletes' physical performance during weight-lifting, cardiorespiratory functioning, and psychomotor tasks that require accuracy and consistent performance. [24][25][26][27] While having naps, sleep extension, and sleep-hygiene practices during season appear advantageous to performance. 28,29 Sleep deprivation has cognitive consequences and can negatively affect physical performance during sport tasks including decision making, reaction time and attention, fine motor coordination, and imprinting memories which are crucial for athletic performance. ...
... Auch die Befunde, dass sich eine geringere Schlafdauer und eine längere Einschlaflatenz darauf auswirken, dass das Training am folgenden Tag als intensiver wahrgenommen wird, decken sich mit vorangegangenen Studien. Diese zeigten sowohl, dass die körperliche Leistung nach schlechter Schlafqualität eingeschränkt ist, als auch eine damit einhergehende höhere subjektive Trainingsbelastung und geringere Vitalität während des Trainings (Fullagar et al., 2015;Reilly & Piercy, 1994;Sinnerton & Reilly, 1992). ...
Zusammenfassung. In dieser Studie wurde das Schlaf-Wach-Verhalten jugendlicher Elite-Mannschaftsathleten in Österreich im Zusammenhang mit deren Training untersucht. Dafür wurden 104 Athleten ( M=14.52 Jahre, SD=0.40), die jeweils Mitglied eines U15/U16 Teams im Fußball ( n=69) oder Eishockey ( n =35) waren, über mehrere Wochen (14 – 42 Tage) per Aktigraphie und Schlafprotokoll untersucht. Zusätzlich wurden der Chronotyp (D-MEQ) und die allgemeine Schlafqualität (PSQI) erhoben. Es wurde angenommen, dass die Schlafqualität vor Trainings- und Spieltagen geringer ist als vor Ruhetagen und dass sich eine geringe Schlafqualität negativ auf die Trainingsintensität auswirkt. Es konnte gezeigt werden, dass die Athleten an Ruhetagen eine längere Schlafdauer aufweisen. Es hat sich außerdem bestätigt, dass eine kürzere Schlafdauer und längere Einschlaflatenz einen negativen Einfluss auf die wahrgenommene Trainingsintensität am folgenden Tag haben. Ein stärkerer Einbezug der Schlafqualität bei Leistungsanalysen und in der Gestaltung von Trainingsplänen wird empfohlen.
... Brotherton et al. (2019), in their extensive study, reported favourable effects of nap on components of bench press and leg press, through improvement in sleepiness, alertness and tiredness. However, variables of bench press were more affected than those of leg press, as a result of effective sleep loss being complex in lifts with higher skill-orientation and with a more significant cognitive component, i.e., bench press in this study (Brotherton et al., 2019;Drust et al., 2005;Reilly & Piercy, 1994). Napping had equivocal effects on grip strength as reported by two studies (Brotherton et al., 2019;Waterhouse et al., 2007), with the inconsistent finding estimated due to differences in nap duration. ...
Background
Sleep is the body’s natural recovery process, restoring routine metabolic and regulatory functions. Various sleep interventions have been developed to facilitate recovery, and athletic performance, and daytime napping are among them. However, due to inconsistencies in studies, it remains unclear whether daytime napping affects sports performance. This article aims to review the effects of daytime napping on various variables of sports performance in physically active individuals with and without partial-sleep deprivation.
Methods
A systematic search in three clinical databases, namely Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, and Web of Science, was conducted. To be included in the current review, the study should be a randomized controlled trial that evaluated the influence of daytime napping on one or more components of sports performance in healthy adults, 18 years old or older.
Results
In the accessible data available until December 2021, 1,094 records were found, of which 12 relevant randomized controlled trials were selected for qualitative synthesis. The majority of studies reported favourable effects of daytime napping on sports performance. However, only one study reported no significant impact, possibly due to a different methodological approach and a shorter nap duration.
Conclusion
Napping strategies optimize sports performance in physically active, athletic populations, benefitting partially sleep-deprived and well-slept individuals, with longer nap durations (~90 min) having more significant advantages. Daytime naps can be considered as cost-efficient, self-administered methods promoting recovery of body functions.
... Insufficient sleep results in compromised athletic performance [11]. Interventional studies controlling for sleep duration have shown that subjective effort (rating of perceived exertion: RPE) during an exercise task progressively increased over subsequent days of sleep restriction (~3 h/night) [35]. Though this was shorter sleep than most of the participants in the current study, these results support the notion that 1 week, or an entire semester, of disrupted sleep via early morning PT may exacerbate the response to exercise. ...
Sleep and circadian rhythms are critically important for optimal physical performance and maintaining health during training. Chronotype and altered sleep may modulate the response to exercise training, especially when performed at specific times/days, which may contribute to musculoskeletal injury. The purpose of this study was to determine if cadet characteristics (chronotype, sleep duration, and social jetlag) were associated with injury incidence and inflammation during physical training. Reserve Officers’ Training Corps (ROTC) cadets (n = 42) completed the Morningness/Eveningness Questionnaire to determine chronotype, and 1-week sleep logs to determine sleep duration and social jetlag. Salivary IL-6 was measured before and after the first and fourth exercise sessions during training. Prospective injury incidence was monitored over 14 weeks of training, and Army Physical Fitness Test scores were recorded at the conclusion. Chronotype, sleep duration, and social jetlag were assessed as independent factors impacting IL-6, injury incidence, and APFT scores using ANOVAs, chi-squared tests, and the t-test where appropriate, with significance accepted at p < 0.05. Evening chronotypes performed worse on the APFT (evening = 103.8 ± 59.8 vs. intermediate = 221.9 ± 40.3 vs. morning = 216.6 ± 43.6; p < 0.05), with no difference in injury incidence. Sleep duration did not significantly impact APFT score or injury incidence. Social jetlag was significantly higher in injured vs. uninjured cadets (2:40 ± 1:03 vs. 1:32 ± 55, p < 0.05). Exercise increased salivary IL-6, with no significant effects of chronotype, sleep duration, or social jetlag. Evening chronotypes and cadets with social jetlag display hampered performance during morning APFT. Social jetlag may be a behavioral biomarker for musculoskeletal injury risk, which requires further investigation.
... These findings align with previous literature where maximal speed, power, and strength have been found to not be negatively impacted by acute sleep deprivation (Blumert et al., 2007;Fullagar et al., 2015;Reilly & Edwards, 2007;Watson, 2017). Interestingly, sustained partial sleep deprivation of three hours' sleep per night over three nights has negatively impacted strength performance in weightlifting athletes (Reilly & Piercy, 1994), suggesting that performance decrements may only arise with sustained sleep deprivation. Sleep deprivation was not observed in the seven nights recorded (Figure 2), as all nights met the recommended sleep durations (Hirshkowitz et al., 2015). ...
... Considering that depression and sleep dysfunction can result in poor performance and increased injury incidence 4,18) , the rapid increase in depression and sleep dysfunction is a problem that must be addressed urgently. Psychosocial interventions, such as cognitive behavioral therapy (CBT) promote positive emotional states and increased rehabilitative adherence, both of which facilitate recovery from injury 19) . ...
This study aimed to observe the conditions of Japanese college athletes during the COVID-19 pandemic for the prevention of psychiatric and sleep disorders. A survey was conducted with 100 players before and after they refrained from sports activities due to the emergency measures (April 7–May 14, 2020) against COVID-19. The survey items used were the Hospital Anxiety and Depression Scale (HADS) for psychiatric symptoms (anxiety and depression) and the Pittsburgh Sleep Quality Index (PSQI) for sleep. A survey on the living conditions was based on a web-based questionnaire. Sleep dysfunction (PSQI ≥ 6), anxiety (HADS-A ≥ 8), and depression (HADS-D ≥ 8) were found in 20 (20%), 19 (19%), and 18 (18%) players before the emergency measures, and 32 (32%), 20 (20%), and 31 (31%) players after emergency measures, respectively. Of the 100 participants, 36 (36%) developed sleep dysfunction or depression as they lived alone, were anxious about school life (e.g., friendships), and were financially unstable regarding living expenses (e.g., not able to work part-time). Due to these findings, it is necessary to actively intervene in the mental health of university students.
... Additionally, research has predominantly investigated males undergoing either total sleep 67 deprivation [for example, (Blumert et al., 2007;Meney, Waterhouse, Atkinson, Reilly, & 68 Davenne, 1998)] or severe sleep restriction (e.g. 3 hours' sleep) during limited periods of 69 time [for example, (Reilly & Piercy, 1994;Souissi et al., 2013)]. Sleep restriction impairs 70 muscle strength in multi-joint, compound exercises (Knowles et al., 2018), which are 71 commonly used by practitioners for their transferability to athletic performance (8). ...
... maximal strength) is fluid, and can be impacted by additional stressors such as poor nutrition, sleep deprivation, and residual fatigue. [46][47][48][49][50] VBT, however, allows practitioners to account for such variation in strength through its basic principles. 45 Participants divulged other benefits of VBT. ...
Velocity-based training (VBT) is a contemporary prescriptive, programming, and testing tool commonly utilised in strength and conditioning (S&C). Over recent years, there has been an influx of peer-reviewed literature investigating several different applications (e.g. load-velocity profiling, velocity loss, load manipulation, and reliability of technology) of VBT. The procedures implemented in research, however, do not always reflect the practices within applied environments. The aim of this study, therefore, was to investigate the perceptions and applications of VBT within elite S&C to enhance contextual understanding and develop appropriate avenues of practitioner-focused research. Fourteen high-performance S&C coaches participated in semi-structured interviews to discuss their experiences of implementing VBT into their practices. Reflexive thematic analysis was adopted, following an inductive and realist approach. Three central organising themes emerged: Technology, applications, and reflections. Within these central themes, higher order themes consisting of drivers for buying technology; programming, testing, monitoring, and feedback; and benefits, drawbacks, and future uses also emerged. Practitioners reported varied drivers and applications of VBT, often being dictated by simplicity, environmental context, and personal preferences. Coaches perceived VBT to be a beneficial tool yet were cognizant of the drawbacks and challenges in certain settings. VBT is a flexible tool that can support and aid several aspects of S&C planning and delivery, with coaches valuing the impact it can have on training environments, objective prescriptions, tracking player readiness, and programme success.
... 23 Further, sleep duration and quality during season were found to have an impact on athletes' physical performance during weight-lifting, cardiorespiratory functioning, and psychomotor tasks that require accuracy and consistent performance. [24][25][26][27] While having naps, sleep extension, and sleep-hygiene practices during season appear advantageous to performance. 28,29 Sleep deprivation has cognitive consequences and can negatively affect physical performance during sport tasks including decision making, reaction time and attention, fine motor coordination, and imprinting memories which are crucial for athletic performance. ...
Background:
There is inconsistency in the relationship between sleeping measures and the occurrence of soccer injuries. Further, most studies investigated sleeping quantity and quality during soccer season but not during off-season. The purpose of this study was to determine the influence of sleeping off-season and during soccer season on the occurrence of injuries in professional soccer players. It was hypothesized that lower sleeping hours and players' thought of inadequate sleeping quantity and quality during off-season and soccer season would associate with the occurrence of soccer injuries.
Methods:
One-hundred and fifty-two professional soccer players (premier league and division I teams, age: 21.82±4.44, BMI: 22.21±2.74, sex: men(n=91), women (n=61)) answered questions related to their sleeping duration and whether that amount of sleep was enough prior to (off-season) and during soccer season. The sleep questions related to sleep quantity were derived from the Arabic Pittsburgh Sleep Quality Index. Players indicated also. Players indicated their injury profile, medical treatment, and time loss due to soccer injury. Sleeping measures were evaluated using univariate and multivariate logistic regression models to determine predictors of soccer injuries.
Results:
Sixty-eight players (44.73%) were injured. Lower total sleeping time during off-season (OR:0.66, 95%CI:0.51-0.85, p=0.002), answering no on "did you regularly get enough sleep during off-season" (OR: 5.64, 95%CI: 2.58-12.27, p<0.001), and answering no on "do you think that your sleeping hours during off-season were enough" (OR:4.76, 95%CI: 1.98-11.46, p=0.001) associated significantly with soccer injuries (R2:38).
Conclusions:
Lower total sleeping time and not getting regularly enough sleeping time during off-season associated with more soccer injuries. This highlights the influence of sleeping quantity and quality off-season on the occurrence of soccer injuries among professional players.
... It appears that efforts of sub-maximal strength requiring sustained exertion has greater vulnerability than a single effort of maximal strength or power. Early work examining this revealed that three nights of sleep reduction decreased sub-maximal and maximal deadlift, bench press, and leg press (Reilly & Piercy, 1994). More recently, effects of 24 hours of sleep deprivation on weightlifting performance were examined in national standard collegiate weightlifters. ...
... During resistance exercise, the extent of fatigue may be dependent on the level of effort [6], type of exercise selection [7], degree of active muscle mass [8], or volume of training [9]. Taking into consideration other variables such as sleep [10] and stress [11], the rate of recovery may dictate the readiness for the subsequent workout. Although less recovery time between each resistance training session (i.e., < 24 h between sessions vs. < 48-72 h between sessions) may not necessarily cause negative outcomes in muscle growth and strength within a short period of time (i.e., 12 weeks) [12], it has been suggested that improper post-exercise recovery or sequence of training may result in an increase in accumulated fatigue [13,14]. ...
It has been suggested that improper post-exercise recovery or improper sequence of training may result in an ‘accumulation’ of fatigue. Despite this suggestion, there is a lack of clarity regarding which physiological mechanisms may be proposed to contribute to fatigue accumulation. The present paper explores the time course of the changes in various fatigue-related measures in order to understand how they may accumulate or lessen over time following an exercise bout or in the context of an exercise program. Regarding peripheral fatigue, the depletion of energy substrates and accumulation of metabolic byproducts has been demonstrated to occur following an acute bout of resistance training; however, peripheral accumulation and depletion appear unlikely candidates to accumulate over time. A number of mechanisms may contribute to the development of central fatigue, postulating the need for prolonged periods of recovery; however, a time course is difficult to determine and is dependent on which measurement is examined. In addition, it has not been demonstrated that central fatigue measures accumulate over time. A potential candidate that may be interpreted as accumulated fatigue is muscle damage, which shares similar characteristics (i.e., prolonged strength loss). Due to the delayed appearance of muscle damage, it may be interpreted as accumulated fatigue. Overall, evidence for the presence of fatigue accumulation with resistance training is equivocal, making it difficult to draw the conclusion that fatigue accumulates. Considerable work remains as to whether fatigue can accumulate over time. Future studies are warranted to elucidate potential mechanisms underlying the concept of fatigue accumulation.
... baseline metrics. 25 However, it should be noted that athletes in this study were sleep restricted for three consecutive nights, and significant changes were only noted following the second night. Studies evaluating anaerobic performance following one single night of sleep deprivation have shown that acute sleep loss yielded no difference in power output or weightlifting performance. ...
Young athletes commonly suffer from both acute and chronic sleep deprivation. This has been linked to increased injury rates and decreased athletic and neurocognitive performance. Conversely, sleep optimization in young athletes can lead to improved athletic performance and greater competitive success, with improvement in metrics such as speed, endurance, reaction time, accuracy, alertness, and overall well-being. When aiming to optimize sleep, key elements such as sleep duration, quality, and regularity must be addressed. Clinicians can assess baseline sleep hygiene in young athletes, and educate them on proper methods to optimize sleep. Such methods include limiting screen time before bed, getting exposure to sunlight in the early morning, maintaining an optimal bedroom temperature, avoiding caffeine, and maintaining a consistent sleep schedule throughout the week.
... Frequent maximum testing could therefore create unwanted fatigue, potentially impacting on performances throughout the year [5]. While this is unlikely to be problematic in settings where 1RMs are relatively stable (e.g., strength sports), maximum strength might fluctuate in athletes competing in these sports due to training priorities [5], sleep [6], nutrition [7], and/or fatigue [8]. As a result, alternative strategies such as 1RM prediction from load-velocity profile (LVP) data might be an effective strategy to manipulate load (i.e., autoregulation), which is thought to be vital to optimize athletic development [9]. ...
The study aim was to compare different predictive models in one repetition maximum (1RM) estimation from load-velocity profile (LVP) data. Fourteen strength-trained men underwent initial 1RMs in the free-weight back squat, followed by two LVPs, over three sessions. Profiles were constructed via a combined method (jump squat (0 load, 30–60% 1RM) + back squat (70–100% 1RM)) or back squat only (0 load, 30–100% 1RM) in 10% increments. Quadratic and linear regression modeling was applied to the data to estimate 80% 1RM (kg) using 80% 1RM mean velocity identified in LVP one as the reference point, with load (kg), then extrapolated to predict 1RM. The 1RM prediction was based on LVP two data and analyzed via analysis of variance, effect size (g/), Pearson correlation coefficients (r), paired t-tests, standard error of the estimate (SEE), and limits of agreement (LOA). p < 0.05. All models reported systematic bias < 10 kg, r > 0.97, and SEE < 5 kg, however, all linear models were significantly different from measured 1RM (p = 0.015 <0.001). Significant differences were observed between quadratic and linear models for combined (p < 0.001; = 0.90) and back squat (p = 0.004, = 0.35) methods. Significant differences were observed between exercises when applying linear modeling (p < 0.001, = 0.67–0.80), but not quadratic (p = 0.632–0.929, = 0.001–0.18). Quadratic modeling employing the combined method rendered the greatest predictive validity. Practitioners should therefore utilize this method when looking to predict daily 1RMs as a means of load autoregulation.
... Elite athletes do not meet the traditional 8 h/night recommendation and have reported sleeping 6.5-6.8 h/night (Lastella et al. 2015;Leeder et al. 2012). A number of studies have reported that sleep deprivation has a negative impact on athletic performance, including weight-lifting, cardiorespiratory functioning, and psychomotor tasks that require consistent accuracy and performance (Edwards and Waterhouse 2009;Mougin et al. 1991;Reilly and Piercy 1994). A recent study also summarises the effects of reduced sleep on athletic performance and shows that sleep deprivation decreases running performance, muscle glycogen concentration, submaximal strength, isokinetic peak torque, minute ventilation, distance covered, sprint times, tennis-serve accuracy, soccer kicking skills, and time to exhaustion (Vitale et al. 2019). ...
... In a study by Pallesen et al. (12) in 2017, it was found that soccer players skills were negatively affected by SD. In addition, Reilly et al. (13) measured the effects of SD on lift performance and concluded that SD could negatively affect performance. While sleep and appetite are in relationship, there is still a controversial between sleep and appetite relationship (14). ...
Objective:
Sleep and awakening are a biological cycle that is affected by physiological function, light and darkness, work programs, and other activities. The vital role of sleep in body function and appetite is essential, and this is especially important for athletes. Meanwhile, the conditions of soccer players are such that they are deprived of sleep, and this is a risk to a professional athlete. The aim of the current study was to examine the effects of overnight sleep deprivation on appetite and physical performance in elite female soccer players.
Materials and Methods:
Twelve elite female soccer players in the premier league of Iran with 10-year history were selected to the study (age: 28.50±3.45 yr, height: 160.50±4.07 cm, weight: 55.12±3.52 kg, body mass index: 21.38±1.06 kg/m2). Subjects were evaluated in two rounds with normal sleep and deprivation of night sleep (DNS) and between these two rounds was also a recovery week. The evaluations included physical performance and appetite.
Results:
DNS had a significant effect on appetite (feeling hungry, full, satiate, and eating desire), reaction time, balance (static and dynamic), anaerobic power (peak power, minimum power, average power, and fatigue index), and aerobic performance (p≤0.05).
Conclusion:
DNS may induce disruptions on the appetite and physical performance of elite soccer players. For these, athletes should take into consideration adequate night sleep before performing physical tasks.
... Intriguingly, though, wellbeing was not rated worse after the SR condition. This is in contrast to previous studies that found aspects of wellbeing such as fatigue, mood, and vigor to be rated lower following acute SR (Reilly & Piercy, 1994;Sinnerton & Reilly, 1992; Souissi et al., Table 1. A comparison of the rate of perceived exertion and external load (as measured by GPS) during match-play for the two conditions (SR vs. CON). ...
Purpose: To investigate the cognitive, physical, and perceptual effects of sleep restriction (SR) in soccer players following a night match. Methods: In a crossover design, nine male soccer players from the English Premier League 2 (age, 21 ± 5 years; height, 1.80 ± 0.75 m; body mass, 74.2 ± 6.8 kg) recorded their sleep quality and quantity with sleep logs and a subjective survey after two night matches (19:00); one where sleep duration was not altered (CON) and one where sleep was restricted by a later bed-time (SR). Countermovement jump height (CMJ), subjective wellbeing (1–5 likert scale for mood, stress, fatigue, sleep, and soreness), and cognitive function were measured at baseline and the morning following the match (+12 h; M + 1). Results: Bed-time was later in SR than CON (02:36 ± 0.17 vs. 22:43 ± 29; P = .0001; ηp² = 0.999) and sleep duration was shorter in SR than CON (5.37 ± 0.16 vs. 8.59 h ± 0.36; P = .0001; ηp² = 0.926). CMJ decreased by ~8% after the match in both SR and CON (P = .0001; ηp2 = 0.915) but there were no differences between the conditions (P > .05; ηp2 = 0.041–0.139). Wellbeing was rated worse after both matches (P = .0001; ηp2 = 0.949) but there were no differences between the trials (P > .05; ηp2 = 0.172–257). SR did not influence cognitive function (P > .05; interaction effects, ηp2 = 0.172–257). Conclusion: SR following a nighttime soccer match does not impair CMJ performance, subjective wellbeing, or cognitive function the following morning.
... Previous evidence suggests that individuals are able to overcome the effects of sleep loss to complete short-duration/explosive exercise, yet are unable to maintain performance in sustained or repeated exercise bouts, probably due to reduced motivation to maintain high-intensity performance. 26 Thus, the level of improvement in sleep during and after travel in the intervention group may have not been large enough to prevent the reductions observed in prolonged intermittent-sprint performance. ...
Purpose:
To assess the efficacy of a combined light exposure and sleep hygiene intervention to improve team-sport performance following eastward long-haul transmeridian travel.
Methods:
Twenty physically trained males underwent testing at 09:00 and 17:00 hours local time on 4 consecutive days at home (baseline) and the first 4 days following 21 hours of air travel east across 8 time zones. In a randomized, matched-pairs design, participants traveled with (INT; n = 10) or without (CON; n = 10) a light exposure and sleep hygiene intervention. Performance was assessed via countermovement jump, 20-m sprint, T test, and Yo-Yo Intermittent Recovery Level 1 tests, together with perceptual measures of jet lag, fatigue, mood, and motivation. Sleep was measured using wrist activity monitors in conjunction with self-report diaries.
Results:
Magnitude-based inference and standardized effect-size analysis indicated there was a very likely improvement in the mean change in countermovement jump peak power (effect size 1.10, ±0.55), and likely improvement in 5-m (0.54, ±0.67) and 20-m (0.74, ±0.71) sprint time in INT compared with CON across the 4 days posttravel. Sleep duration was most likely greater in INT both during travel (1.61, ±0.82) and across the 4 nights following travel (1.28, ±0.58) compared with CON. Finally, perceived mood and motivation were likely worse (0.73, ±0.88 and 0.63, ±0.87) across the 4 days posttravel in CON compared with INT.
Conclusions:
Combined light exposure and sleep hygiene improved speed and power but not intermittent-sprint performance up to 96 hours following long-haul transmeridian travel. The reduction of sleep disruption during and following travel is a likely contributor to improved performance.
... Extension of habitual sleep time of 100 min in collegiate basketball players determined an increase of sprint time, throwing accuracy (+ 9% in the free throw), and a decrease in reaction time, together with decreased perceived fatigue and increased perceived vigour [28]. Partial sleep loss (3 h per day over a 3-day period) does not influence maximal biceps curl but a significant decreasing effect was noted on maximal bench press, leg press, and dead lift in gym-trained subjects [29]. Where large muscle masses are involved, the effect of sleep deprivation is more evident, probably due to a summation effect, not visible in exercise involving smaller muscles with less nervous activation. ...
Purpose
The importance of sleep in enhancing the consolidation of memory for movements has been demonstrated. A possible application of sleep manipulation to sport techniques learning is also potentially helpful for training.
Method
Eligibility criteria encompass the group of studies (cross-sectionals and interventions) on humans correlating sleep with physical performance. A search on the topic was performed in Medline.
Results
After a review of sleep organization and memory systems, an overview of literature specific to learning and sport performance is presented. Building on existing literature, it was found that, in the short period after awakening from a night deprived of sleep, a strong activation of CNS happens possibly due to increased catecholamines secretions. This is thought to benefit performance in sports of short duration where the nervous component is predominant, such as jumping and sprinting. On the contrary, complex cognitive tasks performed in sports such as tennis are instead impaired by sleep deprivation. The same applies for maximal performance in endurance running and weightlifting. Placement of a cognitive challenging training before sleep can therefore benefit the acceleration of the learning process of a novel motor task.
Conclusion
Cognitive and emotionally challenging tasks promote an increase of deep sleep, due to the stress put on the brain during learning. In conclusion, practice and/or rehearsal of complex techniques before sleep appears to accelerate the learning process, increasing accuracy and decreasing error rate. However, few studies exist on specific sport techniques, and further research is needed.
... There are other factors besides training load that should be considered in the effects on relative performance. These may include stress (Bali, 2015), sleep (Reilly & Piercy, 1994;Soussi et al., 2008) ...
Background: The popularity of endurance running events has rapidly increased in recent years with more recreational runners entering the field. How recreational runners train is not well known. Understanding this and the relationship between training and performance in this group of runners is important for prescribing appropriate training to maximise performance and decrease the risk of injury. This forms the underlying theme throughout this thesis.
Aim: The broad aims of this thesis were to better understand the ad libitum training habits of well-trained competitive recreational runners and to determine the relationships between performance, training load, and submaximal heart rate (HR) in this cohort.
Methods: Five inter-related studies were performed to: 1) determine relationships between 56-km race performance and pacing (n = 7,327) in competitive recreational runners; 2) determine relationships between 56-km race performance, pacing, and training load in competitive recreational runners (n = 69); 3) determine the accuracy of GPS sport watches in measuring distance (n = 255); 4) develop a feasible and reliable submaximal running test, and 5) determine relationships between performance on a submaximal running test, training load, and submaximal HR in well-trained competitive recreational runners (n = 29).
Main findings: A group of well-trained competitive recreational runners performed 44 22 km/week (median IQR) in a six-month time frame while training ad libitum. This group had a wide range of inter-individual differences in training load performed even when considering participants who had the same relative marathon performance. The same group of well-trained competitive recreational runners maintained most of their training over a six-month period in a range of 0.81 – 1.14 for the acute: chronic workload ratio (ACWR). When the ACWR values reached > 1.50, it was mainly due to participation in endurance running races (> 21-km). When looking at relative weekly changes in training load, the maximum increase was 30% with only two participants having maximum increases of < 10%. The increases in load were predominantly short term (one to two weeks). Submaximal HR had a negative linear relationship with performance in 21% of the study participants. In those participants, poor performances were associated with a higher submaximal HR. Training load was only related to changes in performance in one participant.
Conclusion: This thesis confirms that no single variable can provide the necessary information on how to adjust training load to maximise performance. Athletes, coaches, and sports scientists need to have a holistic view of stress exposure and how this affects the body. Although we can only speculate, when the participants had a poor performance it may have been due to factors such as lack of motivation, fatigue, mental stress, dehydration, and/or sleep deprivation. It is important for runners, coaches, and sports scientists to approach the training load – recovery balance as being unique for each athlete. Even in a homogenous group of well-trained competitive recreational runners, their ad libitum training load is widely varied and was not associated with performance or ability level. The balance should be adjusted over time based on the athlete’s symptoms.
... Literature exists on the relationship between sleep restriction/deprivation, muscle force generating capacity and fatigue, with often conflicting findings: on one hand, no changes in maximum force were retrieved after one night of sleep deprivation (Skurvydas et al., 2020), on the other hand, reduction in submaximal and maximal weight-lifting capacity was reported after a period of sleep restriction (Reilly and Piercy, 1994;Arnal et al., 2016). Moreover, the exact mechanisms underlying the possible effect of sleep restriction/deprivation on muscle force generating capacity and fatigue are still under debate (Fullagar et al., 2015;Arnal et al., 2016). ...
The effect of sleep-wake rhythm disruption on neuromuscular control and muscle fatigue has received little attention. Because nurse shift work is so varied, including overnight duty, rotating shift schedules, early awakening, and interrupted nocturnal sleep, it offers an interesting model to study this paradigm. It has been investigated so far using only subjective markers. A combined approach based on the simultaneous analysis of surface electromyographic (sEMG) and force signals can objectively detect possible deficits in neuromuscular control and muscle fatigue. With this study we investigated neuromuscular activation and muscle contraction capacity at submaximum and maximum level in nurses working two night-shift schedules and compared them to levels in nurses working entirely in day shifts. Sleep quality and activity levels were also assessed. The study sample was 71 nurses grouped by their shift work schedule: night shift for 5 days (NS 5 , n = 46), night shift for 10 days (NS 10 , n = 9), and only day/swing shift (DS, n = 16). Before and after the shift-work cycle, maximum voluntary contraction (MVC) force and muscle activation, neuromuscular control, and muscle fatigability were measured in the finger flexor muscles. Activity level and sleep quality during the shift-work cycle were recorded with a wrist actigraph. After the shift-work cycles, MVC force and muscle activation were decreased (−11 ± 3% and −33 ± 3%, p < 0.001) as was neuromuscular control (−36 ± 8%, p = 0.007), whereas muscle fatigability was increased (+ 19 ± 9%, p = 0.006) in the NS 5 and the NS 10 group. Sleep quality was lower in the NS 5 and the NS 10 group (−8 ± 1.8% and −15%3, respectively, p < 0.001), while the activity level for the three groups was similar. There was a clear reduction in neuromuscular control and an increase in muscle fatigue in the nurses working the night shift. These findings may inform of work schedule planning or recommendations for devising new recovery strategies to counteract neuromuscular alterations in night shift nurses.
... On the contrary, significant changes in the same performance variables have been found after 4 h of SR (Abedelmalek et al., 2013;Souissi et al., 2013Souissi et al., , 2008 . The same controversial results have also been observed in studies testing muscle strength and power (Reilly & Hales, 1988;Reilly & Piercy, 1994) . ...
Mental fatigue and sleep deprivation are two common conditions in our modern societies, affecting millions of healthy people. Whereas mental fatigue is considered a psychobiological state caused by prolonged and demanding cognitive activities, sleep deprivation can be defined as a brain state caused by at least 24 hours of wakefulness. The first aim of this thesis was to investigate the acute effects of mental fatigue, sleep deprivation and subsequent recovery sleep on endurance exercise performance. The second aim was to evaluate the effects of two innovative training interventions, Brain Endurance Training (BET) and Sleep Deprivation Training (SDT) on endurance performance. It was hypothesized that: 1) 50-min of mentally-demanding cognitive task and 25-h of sleep deprivation would impair endurance performance and that the following night of recovery sleep would be enough to restore rested endurance performance; 2) six weeks of BET (alone) and six weeks of SDT (combined with physical training) would improve endurance performance. The first and second study do not provide reliable evidence that mental fatigue and sleep deprivation reduce endurance performance during a half-marathon and a 20-min cycling time trial, respectively. However, an alternative statistical analysis used in study one, suggests that the hypothesis that mental fatigue is harmful cannot be rejected. The third study shows that BET is not effective in physically-inactive males. The fourth study reveals that SDT in combination with physical training might be beneficial to counteract the effects of sleep deprivation on endurance performance. In conclusion, the findings do not provide statistical evidence of a negative effect of mental fatigue and sleep deprivation on endurance performance. However, it might be prudent to avoid them prior to races. The use of BET alone does not enhance endurance performance. Nonetheless, the combination of SDT with a physical training program might be beneficial in preparation for an endurance/ultra-endurance event. Mental Fatigue and Sleep Deprivation: Effects, Mechanisms, and Countermeasures in Endurance Exercise Performance.
... A decrease in isokinetic strength after 30 h of sleep deprivation in Marine Corps soldiers was noted by Bulbulian et al. [7]. Instead, Reilly and Piercy [8] indicate that submaximal lifting tasks are more affected by sleep loss than are maximal efforts, particularly for the first two nights of successive sleep restriction. Other studies show that sleep deprivation had little effect on muscle strength during resistance exercises. ...
The aim of this study was to investigate the influence of 24-h sleep deprivation on the muscle strength of young, healthy and physically fit people. The research material consisted of physical education students. In total, 67 people participated in the study, including 38 women and 29 men. Respondents were divided into an experimental group “E” of 44 persons subjected to 24-h sleep deprivation and a control group “C” of 23 persons. Students completed the Epworth Sleepiness Scale (ESS) measuring daytime sleepiness. Students performed measurements of the maximum strength of knee joint extensor and flexor muscles. Measurements of muscle strength of flexors and extensors of the knee were taken on a UPR-02 A/S chair with Moment II by Sumer software. ANOVA (analysis of variance) was used to determine the significance of differences between experimental “E” and control “C” group. Statistical significance was defined at the level of p ≤ 0.05. Statistically significant differences were observed in the change of strength levels between groups at the strength moments of right (p < 0.05, η2p = 0.16) and left (p < 0.05, η2p = 0.08) knee muscles extensor. Changes in extensor muscle strength are significant for students with left dominant legs.
... It appears that efforts of sub-maximal strength requiring sustained exertion has greater vulnerability than a single effort of maximal strength or power. Early work examining this revealed three nights of sleep reduction decreased submaximal, and maximal deadlift, bench press, and leg press ( Reilly & Piercy, 1994 ). More recently, effects of 24 hours of sleep deprivation on weightlifting performance were examined in national standard collegiate weightlifters. ...
Finally, the authoritative resource that serious cyclists have been waiting for has arrived. The perfect blend of science and application, Cycling Science takes you inside the sport, into the training room and research lab, and onto the course.
A remarkable achievement, Cycling Science features the following:
Contributions from 43 top cycling scientists and coaches from around the world
The latest thinking on the rider-machine interface, including topics such as bike fit, aerodynamics, biomechanics, and pedaling technique
Information about environmental stressors, including heat, altitude, and air pollution
A look at health issues such as on-bike and off-bike nutrition, common injuries, fatigue, overtraining, and recovery
Help in planning training programs, including using a power meter, managing cycling data, off-the-bike training, cycling specific stretching, and mental training
The latest coaching and racing techniques, including pacing theories, and strategies for road, track, MTB, BMX, and ultra-distance events
In this book, editors and cycling scientists Stephen Cheung, PhD, and Mikel Zabala, PhD, have assembled the latest information for serious cyclists.
... The cadets studied in these papers work shifts, have other requirements when they are not on shift, and experience a notable drop in time available to sleep. Their mean sleep time and drop in sleep quality do not constitute total sleep deprivation, but at some points during the mission they accumulate a sleep debt comparable to PSD (Reilly & Piercy, 1994). In experiments with PSD, a 40-50% reduction in total sleep time is often used over the course of 1 or 2 weeks (Herscovitch & Broughton, 1981;Van Dongen, Maislin, Mullington, & Dinges, 2003). ...
Adult life consists of work, non-work, and sleep. All individuals experience a relationship between how well and how much they sleep and subsequent functioning the next day, and the amount and quality of sleep is determined by external and internal factors. Internal factors include personality, individual sleep patterns, and physiological systems, and external factors include the time available to sleep and the sleep environment. For some individuals, the lines between sleep, non-work, and work are more blurred then others, and external factors shape sleep patterns to a greater extent. This is especially the case for military and naval personnel during combat operations and exercises. The primary aim of this thesis is to provide a framework for understanding how sleep quality and sleep duration affect job performance. The research within is based on four key assumptions. Firstly, that lack of sleep and low quality sleep in general decreases cognitive, emotional, and social functioning, which subsequently negatively influences job performance. Secondly, individuals are affected differently by disturbed sleep quality. Thirdly, that group processes, such as leadership, can moderate the negative impact of disturbed sleep on performance. Lastly, the link between sleep and one’s own and others’ perceived job performance is not uniform for different work-sleep schedules. The thesis investigates these hypotheses in three samples of naval personnel of the Royal Norwegian Navy during active combat operations and during naval training exercises. The first paper tracks sleep quality, as measured by symptoms of insomnia, during a four-month counterpiracy mission in the Gulf of Aden, including measurements before the mission, at the halfway point, and towards the end. It separates the crew of 281 naval personnel into high and low hardiness groups based on the mean hardiness level as measured by the DRS-15-R (Dispositional Resilience Scale 15 Revised). Repeated-measures ANOVA showed that the overall sleep quality and insomnia symptoms among the personnel were highest at the midway point and that the high hardiness group showed a trend of overall better sleep quality. The results also showed a significant interaction of hardiness and time, where the lower hardiness group experienced a stable trend of worse sleep quality, while the high hardiness group showed an increase in sleep problems in the middle of the mission, but fewer problems before and towards the end of the mission. The paper concludes that having a hardy disposition is associated with better sleep quality during a naval mission and that external factors such as operational tempo, stress, and fatigue might remove differences between resilient and less resilient sailors at the midway point of the mission. The second paper aims to elaborate on the hardy advantage identified in paper 1. Insomnia is a multi-faceted construct, and it confounds sleep quality and the next day’s performance. In the second paper, we investigate if the results of paper 1 are due to hardy sailors having better sleep quality and subsequent increased performance (mediation) or if hardy sailors are less affected by disturbed sleep quality as measured by next day performance (moderation). The two hypotheses were tested in a sample of 65 naval cadets during a challenging training exercise using a diary study format. Hardiness was measured with the DRS- 15-R before the mission, daily sleep quality and duration were measured with single sleep diary items, and daily naval work performance was measured by peer ratings of performance. The results were also controlled for individual differences in neuroticism and were obtained using multi-level analysis. The results did not support a hardy advantage due to better sleep quality, but rather that hardy sailors do not show the same deterioration of performance when faced with worsening sleep quality. Highhardiness naval personnel have an overall performance advantage, which increases as the crew experiences a drop in sleep quality. Overall, paper 1 and paper 2 indicate that resilient and hardy naval personnel have a different response to disturbed sleep. This effect might be due to differences in susceptibility to mood and cognitive impairment, but also to increased willfulness and increased engagement of high-performance individuals as the whole crew experiences cumulative fatigue at sea.
The thesis’s third paper explores the role of sleep duration in addition to sleep quality in a sample of 78 naval cadets during a similar type of demanding training exercise as the sample in paper 2. The overall research focus of paper 3 was to uncover the isolated effects of sleep duration and sleep quality on two self-rated performance measures – task performance and contextual work performance – as well as to uncover the possible role of high-quality leadership as a buffer against the effects of disturbed sleep quality on work performance. The possibility of paradoxical negative performance outcomes due to increased sleep is rarely discussed in organizational and military/operational sleep research. However, during extraordinarily demanding 24- hour continuous operations with severe limitations on sleep, increasing sleep might come at the cost of non-task-related work activities. We hypothesized that sleep quality is positively related to both measures of performance, while sleep duration is positively associated with task performance but negatively associated with contextual performance (e.g. helping others or volunteering for extra work). We also hypothesized that perceived high quality transformational leadership negatively moderates both links between sleep quality and performance. The results showed that sleep quality was positively related to both performance measures. Sleep duration was, however, negatively related to contextual work performance but showed no directional relationship with self-rated task performance. In addition, perceived transformational leadership moderated the link between sleep quality and task performance, but not the link between sleep quality and contextual work performance. The results of the study suggest that during challenging work conditions with extraordinary 24-hour shift work, increasing sleep duration is associated with a drop in contextual performance, an effect that leaders and managers should take into account when planning. The results also show how leaders can partially mitigate the negative effects of worsening sleep quality.
In conclusion, the results from paper 1 and paper 2 both suggest that disturbed sleep might cause a drop in work performance and that this drop is partially dependent on the individual’s resiliency to the worsening sleep quality associated with a naval mission. This could inform personnel selection and might provide a framework for increasing sailors’ work capacity when facing high-paced 24-hour operational activity. The results from paper 1 and paper 3 collectively show that sleep quality and duration have different effects in the context of 24-hour operations, and increasing the demands on the crew without any considerations for time available to sleep can decrease work performance because the crew has to prioritize between sleep and work. Additionally, all three papers point to two possible solutions to the inevitability of disturbed sleep during a naval mission – selecting the most resilient crew based on dispositional hardiness and using transformational leadership as a tool to buffer its negative effects.
... For instance, Temesi et al. (48) reported that sleep deprivation affected cycling exercise performance at submaximal intensity; however, no between-condition differences were found for IMVC or VA TMS . These findings are in line with the general observation that sleep deprivation has less effect on maximal performance and maximal strength than on submaximal exercise (7,40,51). The effects of mental fatigue on physical performance is another area of research where the Values are raw (mean Ϯ standard deviation) measures of peak twitch and maximal M-wave (Mmax) area at PRE, immediately POST, and during recovery [ϩ1 min (R1), ϩ2 min (R2), ϩ4 min (R4), and ϩ8 min R8)]. ...
The aim of this study was to investigate differences in neuromuscular function and corticospinal excitability in response to sustained unilateral (UNIL) and bilateral (BIL) isometric maximal voluntary contraction (IMVC) of the knee extensors. Eleven men performed a 1-min sustained IMVC of the knee extensors with one or both legs. Central and peripheral measures of neuromuscular function and corticospinal excitability were assessed via surface electromyography (EMG), peripheral nerve stimulation, and transcranial magnetic stimulation before, immediately after, and during recovery from IMVC. IMVC force and root-mean-squared EMG decreased during the fatiguing 1-min IMVC, with a larger decrease in EMG during BIL. All neuromuscular function indexes decreased significantly after the IMVC ( P < 0.005), but the magnitude of these decreases did not differ between conditions. Changes in corticospinal excitability (motor evoked potential) and inhibition (silent period) did not differ between conditions. In contrast to previous studies utilizing submaximal exercise, no more peripheral fatigue was found after UNIL vs. BIL conditions, even though central drive was lower after BIL 1-min IMVC. Corticospinal excitability and inhibition were not found to be different between UNIL and BIL conditions, in line with maximal voluntary activation.
NEW & NOTEWORTHY The present experiment used peripheral nerve stimulation and transcranial magnetic stimulations during a sustained isometric maximal voluntary contraction to investigate the influence of muscle mass on neuromuscular fatigue. Contrary to previous studies that used submaximal exercise, peripheral fatigue was not found to be greater in unilateral vs. bilateral knee extensions even though central drive was lower during bilateral contractions. Corticospinal excitability and inhibition were not found to be different between unilateral and bilateral conditions.
... 16 Poor sleep affects student-athletes in the academic setting, with an increased risk of academic failure among collegiate students with sleep problems. 10 Negative associations between sleep and physical performance, mental well-being, and cognitive functioning in collegiate athletes 9,23,28,33 have been reported. Further, some research suggests that inadequate sleep is associated with vulnerability to illness, 11 an increased injury risk, and poorer recovery outcomes. ...
Background
Symptoms, cognition, balance, and other domains are commonly assessed at baseline testing as part of comprehensive preseason evaluations among collegiate student-athletes. Although approximately 27% of college students have at least 1 sleep disorder, researchers have yet to examine the role of a preexisting sleep disorder on preinjury baseline performance.
Purpose
To compare athletes with and without a reported history of diagnosed sleep disorders on commonly used baseline concussion assessments.
Study Design
Cross-sectional study; Level of evidence, 3.
Methods
A total of 666 National Collegiate Athletic Association student-athletes completed baseline measures including the Balance Error Scoring System (BESS), Brief Symptom Inventory–18 (BSI-18), Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT), Post-Concussion Symptom Scale (PCSS), Sport Concussion Assessment Tool–5th Edition (SCAT5), and Standardized Assessment of Concussion (SAC). There were 333 athletes with a history of diagnosed sleep disorders who were matched on age, sex, sport, and concussion history to 333 athletes with no history of diagnosed sleep disorders. Participants in both groups had a mean age of 19.89 ± 1.36 years and included 182 (54.7%) male athletes, and 126 (37.8%) reported a history of ≥1 concussions.
Results
A series of 1-way analyses of covariance with Bonferroni corrections revealed significant group differences on the BESS (F 1,559 = 8.88; P < .01); BSI-18 somatization (F 1,640 = 18.48; P < .01), depression (F 1,640 = 18.78; P < .01), anxiety (F 1,640 = 19.42; P < .01), and global severity index (F 1,640 = 27.18; P < .01); PCSS (F 1,424 = 29.42; P < .01); SCAT5 symptom number (F 1,634 = 28.79; P < .01) and symptom severity (F 1,634 = 31.74; P < .01); and SAC (F 1,578 = 4.36; P = .037). Specifically, while the sleep disorder group did perform better on the BESS, they also reported higher symptoms on the BSI-18, PCSS, and SCAT5 and performed worse on the SAC. There were no group differences on ImPACT performance.
Conclusion
Collegiate student-athletes with diagnosed sleep disorders reported elevated affective and concussion symptoms at baseline that could affect the interpretation of postinjury impairments and symptoms. Based on the small effect sizes of our findings, however, the magnitude of these differences is of questionable clinical significance. Still, clinicians should consider diagnosed sleep disorders as reported during preparticipation sports physical examinations when interpreting baseline and postinjury concussion assessments.
Introduction:
Female athletes sleep less and report more sleep problems than males. Inadequate sleep reduces maximal strength in males; however, little is known about the impact of sleep restriction on the quantity and quality of resistance exercise performed by females. This study investigated the effect of nine nights of moderate sleep restriction on repeated resistance exercise performance, hormonal responses and perceived fatigue in females.
Methods:
Ten healthy, resistance-trained, eumenorrheic females aged 18-35 years underwent nine nights of sleep restriction (SR; 5-h time in bed) and normal sleep (NS; ≥7 h time in bed), in a randomised, cross-over fashion with a minimum 6-week washout. Participants completed four resistance exercise sessions per trial, with blood samples collected pre- and post-exercise. Exercise performance was assessed using volume-load, reactive strength index and mean concentric velocity with rating of perceived exertion recorded post-exercise. Participants completed awakening saliva sampling and the multi-component training distress scale daily.
Results:
Volume-load decreased trivially (<1%, p < 0.05) with SR. Mean concentric velocity per set was slower during SR for lower body (up to 15%, p < 0.05), but not upper body, compound lifts. Intra-set velocity loss was up to 7% greater during SR for back squats (p < 0.05). SR increased salivary cortisol area under the curve (by 42%), total training distress (by 84%) and session perceived exertion (by 11%).
Conclusions:
Sustained SR reduces markers of resistance exercise quality (bar velocity) more than quantity (volume-load), and increases perceived effort at the same relative intensity in resistance-trained females. Markers of exercise quality and internal load may be more sensitive than volume-load, to advise coaches to the decline in lifting performance for females experiencing sleep restriction.
Athletic performance is mutually dependent upon individual constraints and practical interventions. Regarding the former, it is recognised that brain activity and sleep indices can modulate movement planning and execution. Concerning the strategies used in practice, contemporary short-term prescriptions have been adopted by conditioning professionals and physiotherapists with the primary intention to acutely enhance musculoskeletal power output or accelerate post-exercise recovery processes. These includes postactivation performance enhancement (PAPE)-based plyometric warm-up and induced cooling (COOL) through ice packs, respectively. However, it remain unknown whether measures of brain dynamics and natural sleep patterns influence skill-related performance in soccer. To date, the literature does not show a consensus for PAPE effectiveness in young populations. Generally, COOL also negatively affects subsequent lower limb movements requiring high force-velocity levels. Based on these assumptions, the general aim of the current thesis was to investigate the influence of internal individual constraints (EEG and sleep-derived indices) and effects of short-term practical interventions (PAPE and COOL) on the movement kinematics and performance aspects of soccer kicking in youth academy players. A series of six studies is presented. These include a literature review, one technical note and four original experimental research articles (two observational and two interventions) in an attempt to answer the questions defined in the research programme. From the data gathered here, it was possible to provide evidence that a) kick testing in studies systematically lacked resemblance to competition environments; b) occipital brain waves during the preparatory phase determines ball placement while late frontal signalling control both ankle joint in impact phase and post-impact ball velocity; c) poor sleep quality and late chronotype preference are linked to subsequent impaired targeting ability; d) acute enhancements achieved via PAPE/plyometric conditioning are purely neuromuscular, being slightly converted into kicking mechanics or performance improvements; e) in a hot environment, repeated high-intensity running efforts impair both ball placement and velocity whilst a local 5-minutes COOL application assists recovery of overall kick parameters and f) a markerless deep learning-based kinematic system appear as reliable alternative in capturing on-field kicking motion patterns. To conclude, both internal individual constraints (EEG and sleep quality) and a short-term practical intervention (cooling quadriceps/hamstrings with ice packs) have an acute impact in kicking performance in youth soccer context. A model integrating evidence from all papers is presented alongside limitations and recommendations for future studies in this field.
Keywords: Technical skill; 3-dimensional kinematics; Accuracy; EEG; Human movement; Motor Control; Biomechanics.
Many types of research over several decades prove that sleep is a significant factor for human performance. The sleep behaviour of sportspersons in
particular is very different from the normal folks or members of other occupational groups such as police and the military, office-going folks.
Henceforth, this study is projected to investigate the changes in sports persons' sleep behaviour due to the COVID-19 lockdown in India. For which,
the survey was conducted among 514 sportspersons representing various Universities (296 male/218 female) across various states of India using a
simple random sampling technique. The composed data were analyzed using a paired samples t-test. The results of this study indicated that the sleep
behaviour of sportspersons was affected during the COVID-19 lockdown in India.
Objective:This study aims to evaluate the effects of melatonin supplementation on the physical and physiological performance following total night sleep deprivation in trained young males.Materials and Methods:Ten trained young males (23.4±1.71 years, 23.96±1.63 kg/m2) participated in four sessions (sessions 1 and 2, nightly habitual sleep; sessions 3 and 4, total night sleep deprivation). Then, using the double-blind design, subjects were divided into two groups of who took melatonin supplement (10 mg) and placebo, respectively. The subjects were tested by the implementation of the sleep protocol. Then, they consumed the supplement and waited for 30-45 min for secondary measurements. In each measurement, physical and physiological performances were evaluated.Results:Total night sleep deprivation application resulted in a significant decrease in the salivary level of melatonin and impairment in static and dynamic balance, auditory reaction time, jump, upper body, lower body and handgrip strength performance (p
Objective:
To study sleep quality and sleep hygiene in professional athletes and an age-matched cohort.
Design:
Cross-sectional study.
Setting:
Professional athletes and a sport medicine center.
Participants:
Professional rugby, netball and football athletes (n = 184) and attendees to a sport medicine center (n = 101).
Interventions:
Participants completed an online survey.
Main outcome measures:
Sleep Hygiene Index (SHI) and Pittsburgh Sleep Quality Index (PSQI).
Results:
Forty-five percent (n = 128) of respondents were aged between 18 and 24 years, 54% (n = 154) were men and 65% (n = 184) were professional athletes. The sleep duration of the professional athletes (mean rank 134.3, n = 181) was greater than the age-matched cohort (mean rank = 154.4, n = 101), U = 7835.0, z = -2.3, P = 0.02; however, they reported more sleep disturbance (mean ranking = 148.0, n = 181) than the age-matched cohort (mean rank = 129.8, n = 101), U = 7960.5 z = -2.5, P = 0.01, 2-tailed. Professional athletes had worse sleep regularity (mean rank = 152.3, n = 183) compared with the age-matched cohort (mean rank = 124.6, n = 101), U = 7448.5, z = -2.7, P = 0.006, 2-tailed, had an inferior sleep environment (mean rank = 149.5, n = 183) compared with the age-matched cohort (mean rank = 129.8, n = 101), U = 7959.5, z = -2.0, P = 0.047, and had more naps (mean rank = 156.2, n = 183) compared with the age-matched cohort (mean rank = 117.6, n = 101), U = 6729.0, z = -4.2, P = 0.00 0, 2-tailed.
Conclusions:
Professional athletes reported poorer sleep quality and sleep hygiene compared with an age-matched cohort, and difficulty falling asleep following competition. It is likely this is due to the stress of competition, training, and traveling. Because sleep plays an important role in postexercise recovery and has an impact on injury and athletic performance, it is important to have strategies to support better sleep quality and sleep hygiene in athletes.
We recently demonstrated that sleeping on high rebound [HR] mattress toppers induced a continuous and more rapid decline in core body temperature compared to low rebound [LR] mattress toppers during the initial phase of nocturnal sleep in young healthy volunteers. HR toppers are characterized by their supportive feel and high breathability whereas LR toppers are pressure-absorbing. In the current study, we evaluated effects of HR mattress toppers on objectively-(actigraphy) and subjectively-(questionnaires) evaluated sleep, vigilance (psychomotor vigilance test), and athletic performance (40-m sprint time, long jump distance, and star drill time) in youth male athletes age 10–19, in two sessions: fifty-one subjects in 2013 (study I) and 23 subjects in 2014 (study II). Sleeping on HR mattress toppers for four to six weeks improved some athletic performance measures compared to sleeping on LR or sleeping directly on spring mattresses without a topper. Statistically significant improvements in 40-m sprint time in study I (compared to LR) and in star drill time in study II (no topper) were observed. No changes in sleep and psychomotor vigilance were observed. These results suggest selecting optimal sleep surfaces may contribute to the maximization of athletic performances, and further studies are warranted.
Background/Purpose
Despite the importance of sleep for athletic performance, there is a lack of normative sleep data and sex comparisons in collegiate athletes. The primary purpose of our study was to assess the prevalence of insufficient sleep in collegiate athletes, with a secondary aim to compare male and female athletes.
Procedures
Participants included 121 collegiate athletes (65 men and 56 women) from six team sports and three individual sports. Subjective assessments of sleep included at-home sleep diary, Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), and Insomnia Severity Index (ISI). Objective assessments of sleep included three consecutive off-season weekdays of wrist actigraphy to assess total sleep time (TST) and sleep efficiency (SE).
Main Findings
Actigraphy revealed that 94% of student-athletes received <8 hours of sleep/night, while 61% received <7 hours/night. Subjective assessments revealed that 35% had PSQI >5, 28% had ISI scores >7, and 19% had ESS scores >10. Objective TST was not different between sexes (6.7±0.1 vs. 6.7±0.1 hours, p=0.99), but females demonstrated higher SE (87±1 vs. 82±1%, p<0.01) and lower WASO (31±2 vs. 38±2 min, p=0.02). Male athletes significantly overestimated TST (i.e., subjective minus objective TST) when compared to female athletes (Δ0.7±0.1 vs. Δ0.3±0.1 hours/night; p<0.01). PSQI, ISI, and ESS were not different between sexes.
Conclusions
The majority of male and female collegiate athletes received less than age-recommended levels of sleep, and 44% subjectively reported poor sleep quality, mild severity insomnia, and/or excessive daytime sleepiness. Sex differences were observed in male and female collegiate athletes.
Shattock, K and Tee, JC. Autoregulation in resistance training: A comparison of subjective versus objective methods. J Strength Cond Res XX(X): 000-000, 2020-Autoregulation (AR) is a resistance training periodization approach that adjusts training prescription in response to individual rates of athlete adaptation. AR training prescription can make use of either subjective (rating of perceived exertion [RPE]) or objective (barbell velocity) intensity descriptors. The aim of this research was to compare the efficacy of these 2 approaches in improving sport-specific physical performance measures. Using a randomized crossover design, 20 amateur rugby union players completed two 6-week blocks of training with training intensity prescribed using either objective velocity-based (VB) (measured using a wearable accelerometer device) or objective RPE-based intensity prescriptions. Training volume was matched for both groups while training intensity was equivalent but prescribed using either VB or RPE measures. Performance measurements were countermovement jump (CMJ), 1 repetition maximum back squat and bench press, and 10-, 20-, and 40-m sprint. Testing was conducted before and immediately after each training block. The likelihood that observed changes in performance measures were meaningful was assessed using magnitude-based decisions. Both training programs induced practically meaningful improvements in CMJ (VB most likely +8.2, ±1.1%; RPE likely +3.8, ±0.9%), back squat (VB most likely +7.5, ±1.5%; RPE possibly +3.5, ±1.8%), and bench press (VB most likely +7.7, ±2.1%; RPE possibly +3.8, ±0.9%). Changes in sprint test performance were very likely trivial for both programs. Objective AR programming resulted in larger improvements in CMJ (likely 4.2, ±1.2%), squat (likely 3.7, ±1.5%) performance, and bench press (possibly 3.7, ±1.5%) performance. Autoregulation periodization improved strength and CMJ, but not sprint performance. Autoregulation effects are augmented through the use of objective intensity prescription.
Distinguishes 6 factors in the working situation influencing the effect of environmental stress upon performance: (1) the duration of work on the task, (2) the familiarity of the operator with the stress and with the work he has to do under stress, (3) the level of incentive of the operator, (4) the kind of work he has to do, (5) the aspect of performance which is most important, and (6) the presence of other stresses in the working situation. The examples taken to illustrate the importance of these factors come from only 4 stresses: heat, loss of sleep, noise, and alcohol. (61 ref.)
6 Ss worked a full day, mainly on vigilance and calculation tests, for 2 successive days in each of 6 successive wk. On the preceding nights they were allowed 0, 1, 2, 3, 5, or 7.5 hr. sleep varying according to the week of testing. Less than 5 hr. sleep on a single night impaired vigilance; less than 3 hr. impaired calculation. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Investigated the responses of a 31-yr-old male athlete to continuous paced work at moderate intensity for 100 hrs under conditions of controlled liquid and energy intake. Heart rate (HR) increased at first, then gradually declined to reach a steady state after 44 hrs. Lung function (vital capacity and forced expiratory volume) and reaction time showed a significant deteriorating trend over the experimental period. HR, lung function, and reaction time were significantly intercorrelated. Subjective time perception was correlated with reaction time and HR. Blood glucose levels were not related to any of the other variables. None of the variables exhibited a circadian rhythm. Periodicities over 8, 48, and 96 hr cycles were observed in lung function. Scores in 2 mental performance tests were not greatly affected over the duration of the experiment. (31 ref) (PsycINFO Database Record (c) 2012 APA, all rights reserved)
The effect of 60 h of sleep deprivation (SD) upon physical performance and physiological responses to exercise was examined in 11 male subjects. The experiment consisted of two conditions separated by at least 10 d. In the experimental condition (E) subjects remained awake for 60 h and in the control condition (C) the same subjects had 7 h of sleep per night. In both conditions subjects reported to the laboratory on the evening prior to d 1 and slept for 7 h. Physical performance testing was carried out on d 1 and again on d 3 after either two nights of sleep or two nights of SD. Results obtained on d 3 are expressed relative to d 1, the control day. Maximal isometric and isokinetic muscular strength and endurance of selected upper and lower body muscle groups, performance of the Wingate Anaerobic Power Test, simple reaction time, the blood lactate response to cycle exercise at 70% VO2max, and most of the cardiovascular and respiratory responses to treadmill running at 70% and 80% VO2max, were not significantly altered as a result of SD. These results suggest that sleep loss of up to 60 h will not impair the capability for physical work, a finding of considerable importance in sustained military operations which frequently involve the combination of both physical and mental tasks.
Human capabilities in manual materials-handling activities may be influenced by a number of task variables. The psychophysical method of Snook (1978) was used to determine the effects of load and lifting frequency upon workloads selected by eight male soldiers. The subjects repeatedly lifted and lowered a box (38 × 55 × 24 cm) to and from a platform set at 40% stature for 10 minutes and either adjusted the load, or the lifting frequency, or a combination of both variables in order to select a workload which they considered to be a maximum acceptable workload (MAWL) for a work-period of one hour. When the lifting frequency was adjusted, the mean MAWL was 94·5 kg m min (S.D. 28·4). This was significantly greater (P ≤ 0·05) by 27% than when the load alone was adjusted (74·3 kg m min , S. D. 23·3). Control of both variables together produced a MAWL of 76·5 kg m min (S. D. 24·1) which was similar to that selected when the load alone was adjusted.When the soldiers lifted and lowered their selected workloads for a one-hour work-period, the average heart rate was 101 beats min and the mean oxygen cost was 23·3% of their maximal oxygen uptake (determined by cycle ergometry). The work intensity was subjectively assessed as ‘Fairly Light’ using the Rating of Perceived Exertion scale (Borg 1971). In spite of significant differences between the MAWLs selected by the adjustment of the two variables, the physiological measurements and subjective assessments made whilst lifting these workloads were not significantly different. This suggests that other factors may influence an individual's perception of MAWL.The results in this study may have been affected by limitations imposed by the experimental design. However, they do suggest that the frequency of lifting could be a more appropriate variable to manipulate in the self-selection of workloads.
The effects of physical exercise and sleep deprivation on mood and cognitive performance were studied in 12 healthy young male volunteers deprived of sleep on two occasions. During the first 60-hr period without sleep, half of the subjects walked on a treadmill at 25–30% of their maximum aerobic capacity (Exercise condition) for 1 out of every 3 hrs while the remaining 6 subjects remained physically inactive (No Exercise condition) during that same hour. Eight weeks later the same 12 subjects underwent an identical sleep-deprivation protocol except that those who were previously inactive exercised, while those who previously exercised remained inactive. Throughout the sleep deprivation periods, subjects in both conditions completed subjective assessments of fatigue, sleepiness and mood every 3 hrs, performed an auditory vigilance task every 6 hrs, and completed a cognitive test battery every 12 hrs. The results revealed clear decrements in mood and performance as a function of sleep loss. However, with the exception of somewhat more long reaction times in the Exercise condition, exercise neither increased nor decreased the impairment induced by sleep deprivation.
Muscular performance was tested during 64 hours of sleep deprivation with and without intermittent excercise (treadmill walking at 28% of maximum oxygen intake). The subjects (12 males aged 22·7 ± 2·2 years) carried out a cross-over trial with an 8 week interval separating the two periods of sleep deprivation. The sleep deprivation did not change the time for a 40 m dash, isometric handgrip force or balance (stabilometer test). Vertical jump height decreased, the change being significant for simple sleep deprivation, but not for the combination of deprivation and intermittent exercise. Sleep deprivation decreased isokinetic extension force at 60° s−1, while intermittent walking decreased isokinetic extension force at both 60 and 180° −1; however, there was no significant difference between exercise plus sleep deprivation and sleep deprivation alone at either angular velocity. We conclude that the moderate intensity of physical activity likely in industrial work has little influence upon human performance under conditions of sleep deprivation.
Sleep is commonly viewed to be a state of enhanced tissue growth and repair ('restitution'), following the wear and tear of wakefulness. One of the major findings appearing to support this hypothesis is that for certain hormones, which amongst their various activities have anabolic action, a heightened release is displayed during human sleep, and prominent within this group is human growth hormone (hGH). The substantial sleep-hGH output is mostly associated with the deep form of non-dreaming sleep (usually referred to as slow wave sleep, SWS, because of its EEG characteristics), found in the first few hours of sleep. However, the significance of the sleep-hGH release for this restitution starts to become obscure when one notes that other hormones integral to anabolism, such as insulin, display no sleep-related release. As will be seen, there are several other findings which have been taken as signs of this restitution, which on further analysis turn out to be misleading in this respect. In fact it is beginning to appear that for the majority of tissues, excluding the brain, sleep may well be a state of tissue degradation, owing to the night-time fast.
There is a great demand for perceptual effort ratings in order to better understand man at work. Such ratings are important complements to behavioral and physiological measurements of physical performance and work capacity. This is true for both theoretical analysis and application in medicine, human factors, and sports. Perceptual estimates, obtained by psychophysical ratio-scaling methods, are valid when describing general perceptual variation, but category methods are more useful in several applied situations when differences between individuals are described. A presentation is made of ratio-scaling methods, category methods, especially the Borg Scale for ratings of perceived exertion, and a new method that combines the category method with ratio properties. Some of the advantages and disadvantages of the different methods are discussed in both theoretical-psychophysical and psychophysiological frames of reference.
Acute loss of sleep produces few apparent physiological effects at rest. Nevertheless, many anecdotes suggest that adequate sleep is essential for optimum endurance athletic performance. To investigate this question, heavy exercise performance after 36 h without sleep was compared with that after normal sleep in eight subjects. During prolonged treadmill walking at about 80% of the\(\dot V_{O_2 } \) max, sleep loss reduced work time to exhaustion by an average of 11% (p=0.05). This decrease occurred despite doubling monetary incentives for subjects during work after sleeplessness. Subjects appeared to fall into “resistant” and “susceptible” categories: four showed less than a 5% change in performance after sleep loss, while four others showed decrements in exercise tolerance ranging from 15 to 40%. During the walk, sleep loss resulted in significantly greater perceived exertion (p<0.05), even though exercise heart rate and metabolic rate (\(\dot V_{O_2 } \) and\(\dot V_{CO_2 } \)) were unchanged. Minute ventilation was significantly elevated during exercise after sleep loss (p<0.05). Sleep loss failed to alter the continuous slow rises in\(\dot V_E \)
E and heart rate that occurred as work was prolonged. These findings suggest that the psychological effects of acute sleep loss may contribute to decreased tolerance of prolonged heavy exercise.
Sleep loss alters the perceptual response to exercise: subjects describe constant external work loads as more severe after sleep deprivation. However, since subjects cannot be "blind" to their sleep status and have knowledge of previous exertional ratings, it remains unknown if this increase in perceived exertion merely represents expectations of increased difficulty of exercise after sleep loss. As one approach to this problem, we asked 24 subjects to produce equivalent "very hard" efforts, once after normal sleep, and once after 30 h without sleep. This was done by allowing the subject, while walking at constant speed, to adjust treadmill grade, without knowledge of the actual elevation. We found that exercise at equal perceived exertion was associated with the choice of a nearly equal absolute work load after sleep deprivation as after normal sleep (17.1 vs. 17.5% grade; p = n.s.). In addition, after 10 min of exercise at the self-selected intensity, subjects displayed identical ventilation, oxygen uptake, and CO2 production. However, heart rate was significantly lower during exercise after sleep loss (170 +/- 3 vs. 178 +/- 3 b X min-1; p less than 0.001). These results suggest that previously measured increases in perceived exertion during constant-load exercise after sleep loss may be spurious.
Psychophysical basis of perceived exertion Human sleep and tissue restitution; some qualifications and doubts
- G 1 Borg
- E Hoddes
- W Dement
- V Zaroche
- J A Horne
BORG, G. 1982, Psychophysical basis of perceived exertion, Medicine and Science in Sports and Exercise, 14, 377-38 1. HODDES, E., DEMENT, W. and ZAROCHE, V. 1973, Development and use of the Stanford Sleepiness Scale, Psychophysiology. 9, 150. HORNE, J. A. 1983, Human sleep and tissue restitution; some qualifications and doubts, Clinical Science, 65, 569-578.