To Sleep Dreaming Medals: Sleep Characteristics, Napping Behavior, and Sleep-Hygiene Strategies in Elite Track-and-Field Athletes Facing the Olympic Games of Tokyo 2021.

PURPOSE: Few data are available on sleep characteristics of elite track-and-field athletes. Our study aimed to assess (1) differences in sleep between sexes and among different track-and-field disciplines, (2) the effect of individualized sleep-hygiene strategies on athletes' sleep parameters, and (3) daytime nap characteristics in track-and-field athletes. METHODS: Sleep characteristics of 16 elite Olympic-level track-and-field athletes (male: n = 8; female: n = 8) were assessed during the preseason period, at baseline (T0), and during the in-season period, after the adoption of individualized sleep-hygiene strategies (T1). Sleep parameters were objectively monitored by actigraphy for a minimum of 10 days, for each athlete, at both T0 and T1. A total of 702 nights were analyzed (T0 = 425; T1 = 277). RESULTS: Female athletes displayed better sleep efficiency (88.69 [87.69-89.68] vs 91.72 [90.99-92.45]; P = .003, effect size [ES]: 0.44), lower sleep latency (18.99 [15.97-22.00] vs 6.99 [5.65-8.32]; P < .001, ES: 0.65), higher total sleep time (07:03 [06:56-07:11] vs 07:18 [07:10-07:26]; P = .030, ES: 0.26), earlier bedtime (00:24 [00:16-00:32] vs 00:13 [00:04-00:22]; P = .027, ES: 0.18), and lower nap frequency (P < .001) than male athletes. Long-distance runners had earlier bedtime (00:10 [00:03-00:38] vs 00:36 [00:26-00:46]; P < .001, ES: 0.41) and wake-up time (07:41 [07:36-07:46] vs 08:18 [08:07-08:30]; P < .001, ES: 0.61), higher nap frequency, but lower sleep efficiency (88.79 [87.80-89.77] vs 91.67 [90.95-92.38]; P = .013, ES: 0.44), and longer sleep latency (18.89 [15.94-21.84] vs 6.69 [5.33-8.06]; P < .001, ES: 0.67) than athletes of short-term disciplines. Furthermore, sleep-hygiene strategies had a positive impact on athletes' total sleep time (429.2 [423.5-434.8] vs 451.4 [444.2-458.6]; P < .001, ES: 0.37) and sleep latency (14.33 [12.34-16.32] vs 10.67 [8.66-12.68]; P = .017, ES: 0.19). CONCLUSIONS: Sleep quality and quantity were suboptimal at baseline in Olympic-level track-and-field athletes. Large differences were observed in sleep characteristics between sexes and among different track-and-field disciplines. Given the positive effect of individualized sleep-hygiene strategies on athlete's sleep, coaches should implement sleep education sessions in the daily routine of top-level athletes.

Lockdown Duration and Training Intensity Affect Sleep Behavior in an International Sample of 1,454 Elite Athletes.

Objective: To investigate the effect of 1) lockdown duration and 2) training intensity on sleep quality and insomnia symptoms in elite athletes. Methods: 1,454 elite athletes (24.1 ± 6.7 years; 42% female; 41% individual sports) from 40 countries answered a retrospective, cross-sectional, web-based questionnaire relating to their behavioral habits pre- and during- COVID-19 lockdown, including: 1) Pittsburgh sleep quality index (PSQI); 2) Insomnia severity index (ISI); bespoke questions about 3) napping; and 4) training behaviors. The association between dependent (PSQI and ISI) and independent variables (sleep, napping and training behaviors) was determined with multiple regression and is reported as semi-partial correlation coefficient squared (in percentage). Results: 15% of the sample spent < 1 month, 27% spent 1-2 months and 58% spent > 2 months in lockdown. 29% self-reported maintaining the same training intensity during-lockdown whilst 71% reduced training intensity. PSQI (4.1 ± 2.4 to 5.8 ± 3.1; mean difference (MD): 1.7; 95% confidence interval of the difference (95% CI): 1.6-1.9) and ISI (5.1 ± 4.7 to 7.7 ± 6.4; MD: 2.6; 95% CI: 2.3-2.9) scores were higher during-compared to pre-lockdown, associated (all p < 0.001) with longer sleep onset latency (PSQI: 28%; ISI: 23%), later bedtime (PSQI: 13%; ISI: 14%) and later preferred time of day to train (PSQI: 9%; ISI: 5%) during-lockdown. Those who reduced training intensity during-lockdown showed higher PSQI (p < 0.001; MD: 1.25; 95% CI: 0.87-1.63) and ISI (p < 0.001; MD: 2.5; 95% CI: 1.72-3.27) scores compared to those who maintained training intensity. Although PSQI score was not affected by the lockdown duration, ISI score was higher in athletes who spent > 2 months confined compared to those who spent < 1 month (p < 0.001; MD: 1.28; 95% CI: 0.26-2.3). Conclusion: Reducing training intensity during the COVID-19-induced lockdown was associated with lower sleep quality and higher insomnia severity in elite athletes. Lockdown duration had further disrupting effects on elite athletes' sleep behavior. These findings could be of relevance in future lockdown or lockdown-like situations (e.g., prolonged illness, injury, and quarantine after international travel).

Ramadan Observance Exacerbated the Negative Effects of COVID-19 Lockdown on Sleep and Training Behaviors: A International Survey on 1,681 Muslim Athletes.

Objective: Disrupted sleep and training behaviors in athletes have been reported during the COVID-19 pandemic. We aimed at investigating the combined effects of Ramadan observance and COVID-19 related lockdown in Muslim athletes. Methods: From an international sample of athletes (n = 3,911), 1,681 Muslim athletes (from 44 countries; 25.1 ± 8.7 years, 38% females, 41% elite, 51% team sport athletes) answered a retrospective, cross-sectional questionnaire relating to their behavioral habits pre- and during- COVID-19 lockdown, including: (i) Pittsburgh sleep quality index (PSQI); (ii) insomnia severity index (ISI); (iii) bespoke questions about training, napping, and eating behaviors, and (iv) questions related to training and sleep behaviors during-lockdown and Ramadan compared to lockdown outside of Ramadan. The survey was disseminated predominately through social media, opening 8 July and closing 30 September 2020. Results: The lockdown reduced sleep quality and increased insomnia severity (both p < 0.001). Compared to non-Muslim (n = 2,230), Muslim athletes reported higher PSQI and ISI scores during-lockdown (both p < 0.001), but not pre-lockdown (p > 0.05). Muslim athletes reported longer (p < 0.001; d = 0.29) and later (p < 0.001; d = 0.14) daytime naps, and an increase in late-night meals (p < 0.001; d = 0.49) during- compared to pre-lockdown, associated with lower sleep quality (all p < 0.001). Both sleep quality (χ2 = 222.6; p < 0.001) and training volume (χ2 = 342.4; p < 0.001) were lower during-lockdown and Ramadan compared to lockdown outside of Ramadan in the Muslims athletes. Conclusion: Muslim athletes reported lower sleep quality and higher insomnia severity during- compared to pre-lockdown, and this was exacerbated by Ramadan observance. Therefore, further attention to Muslim athletes is warranted when a circadian disrupter (e.g., lockdown) occurs during Ramadan.

The impact of foot angle on lower limb muscles activity during the back squat and counter movement jump.

BACKGROUND: Squatting is a core exercise for many purposes. However, there is still controversy surrounding the practice of targeting specific muscle groups when performing the back squat with different stance widths or foot positions. Therefore, this study aimed to assess lower limb muscle activation during different form of back squat when adopting three different foot angles. METHODS: Eight male active participants (age: 24.0±0.8 years, height: 1.80±0.63 m and mass: 85.8±8.7kg) performed maximal isometric squat, back squat with an overalod of 80% of 1 repetition maximum, and countermovement jump (CMJ) when adopting three foot rotation angles: parallel (0°), +10° outward (external rotation), and +20° outward (external rotation). We calculated the root mean square of the electromyographic signals recorded from eight participant's dominant leg muscles. RESULTS: During the descending phase of the back squat, the 20° external foot rotation elicited greater activation of the biceps femoris (+35%; P=0.027) and gastrocnemius medialis (+70%; P=0.040) compared to parallel foot. There were no significant differences among the other muscles and exercise conditions. CONCLUSIONS: The +20° foot position increased BF and GasM muscle activity only during the downward phase of the back squat. Strength coaches should consider the present findings when selecting specific resistance exercises aiming to improve athletes' strength and physical fitness.

Incidence of injuries in semi-professional soccer: a six-month retrospective study in the Italian fourth division.

BACKGROUND: Soccer is one of the most popular sports in the world involving about 200 million athletes. Injury management in soccer is crucial for performance and for the costs related to rehabilitation and absence from official matches. While there is quite an exhaustive literature regarding injuries in professional soccer, for amateur soccer the incidence of injuries remains unknown. The purpose of this study was to analyze the prevalence of injuries in the fourth Italian soccer division during the competitive season. METHODS: Medical staff completed an injury report every two months during the competitive season of the fourth Italian soccer division (14 teams, N.=278). The specific description of the problem, player field-position, number of training losses and number of match losses were collected for each player. The time periods were September/October (T1) November/December (T2), January/February (T3). RESULTS: A significant association between injury type and the period of the season was observed: muscle and tendon injuries were the most prevalent injury type (48.9%) in all three periods (χ2 [10] = 33.86, P<0.001). Overall, 108 (39.7%) injuries occurred at T1, 90 (33.1%) at T2 and 74 (27.2%) at T3 (χ2 [12] = 20.32, P=0.071). CONCLUSIONS: Coaches and athletic trainers should be aware of this greater injury risk when preparing a training program for the season, to implement injury prevention protocols for the most prevalent injury types.

Managing Travel Fatigue and Jet Lag in Athletes: A Review and Consensus Statement.

Athletes are increasingly required to travel domestically and internationally, often resulting in travel fatigue and jet lag. Despite considerable agreement that travel fatigue and jet lag can be a real and impactful issue for athletes regarding performance and risk of illness and injury, evidence on optimal assessment and management is lacking. Therefore 26 researchers and/or clinicians with knowledge in travel fatigue, jet lag and sleep in the sports setting, formed an expert panel to formalise a review and consensus document. This manuscript includes definitions of terminology commonly used in the field of circadian physiology, outlines basic information on the human circadian system and how it is affected by time-givers, discusses the causes and consequences of travel fatigue and jet lag, and provides consensus on recommendations for managing travel fatigue and jet lag in athletes. The lack of evidence restricts the strength of recommendations that are possible but the consensus group identified the fundamental principles and interventions to consider for both the assessment and management of travel fatigue and jet lag. These are summarised in travel toolboxes including strategies for pre-flight, during flight and post-flight. The consensus group also outlined specific steps to advance theory and practice in these areas.

To Nap or Not to Nap? A Systematic Review Evaluating Napping Behavior in Athletes and the Impact on Various Measures of Athletic Performance.

PURPOSE: The objective of this systematic review was to 1) determine how studies evaluated napping behavior in athletes (frequency, duration, timing and measurement); 2) explore how napping impacted physical performance, cognitive performance, perceptual measures (eg, fatigue, muscle soreness, sleepiness and alertness), psychological state and night-time sleep in athletes. METHODS: Five bibliographic databases were searched from database inception to 11 August 2020. Observational and experimental studies comprising able-bodied athletes (mean age ≥12 years), published in English, in peer-reviewed journal papers were included. The Downs and Black Quality Assessment Checklist was used for quality appraisal. RESULTS: Thirty-seven studies were identified of moderate quality. Most studies did not include consistent information regarding nap frequency, duration, and timing. Napping may be beneficial for a range of outcomes that benefit athletes (eg, physical and cognitive performance, perceptual measures, psychological state and night-time sleep). In addition, napping presents athletes with the opportunity to supplement their night-time sleep without compromising sleep quality. CONCLUSION: Athletes may consider napping between 20 to 90 min in duration and between 13:00 and 16:00 hours. Finally, athletes should allow 30 min to reduce sleep inertia prior to training or competition to obtain better performance outcomes. Future studies should include comprehensive recordings of nap duration and quality, and consider using sleep over a 24 hour period (daytime naps and night-time sleep period), specifically using objective methods of sleep assessment (eg, polysomnography/actigraphy).

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

PURPOSE: Little is known about the effect of sleep restriction (SR) on different domains of athletes' physical performance. Therefore, the aim of this randomized, counterbalanced, and crossover study was to evaluate the effect of acute SR on sport-specific technical and athletic performance in male junior tennis players. METHODS: Tennis players (N = 12; age 15.4 ± 2.6 y) were randomly allocated to either a sleep-restriction condition (SR, n = 6), where they experienced acute sleep restriction the night before the test session (≤5 h of sleep), or to a control condition (CON, n = 6), where they followed their habitual sleep-wake routines. Testing procedures included 20 left and right serves, 15 forehand and backhand crosscourt shots, and a repeated-sprint-ability test (RSA). The accuracy of serves and shots was considered for further analysis. One week later, players of SR joined CON, and players of CON experienced SR, and all test procedures were repeated. RESULTS: Significant decrease in the accuracy of right (-17.5%, P = .010, effect size [ES] = 1.0, moderate) and left serve (-14.1%, P = .014, ES = 1.2, large), crosscourt backhand (-23.9%, P = .003, ES ≥ 2.0, very large), and forehand shot (-15.6%, P = .014, ES = 1.1, moderate) were observed in SR compared to CON, while RSA was similar in both conditions. CONCLUSION: Coaches and athletes at the team and individual level should be aware that 1 night of SR affects sport-specific but not athletic performance in tennis players.

Direct superior approach versus posterolateral approach in total hip arthroplasty: a randomized controlled trial on early outcomes on gait, risk of fall, clinical and self-reported measurements.

Background and purpose - Several surgical approaches are used in primary total hip arthroplasty (THA). In this randomized controlled trial we compared gait, risk of fall, self-reported and clinical measurements between subjects after direct superior approach (DSA) versus posterolateral approach (PL) for THA.Patients and methods - Participants with DSA (n = 22; age 74 [SD 8.9]) and PL (n = 23; age 72 [7.7]) underwent gait analysis, risk of fall assessment and Timed Up and Go Test (TUG) before (PRE), 1 month (T1) and 3 months after (T3) surgery. Data on bleeding and surgical time was collected.Results - DSA resulted in longer surgical times (90 [14] vs. 77 [20] min) but lower blood loss (149 [66] vs. 225 [125] mL) than PL. DSA had lower risk of fall at T3 compared with T1 and higher TUG scores at T3 compared with T1 and PRE. PL improved balance at T3 compared with T1 and PRE. Spatiotemporal gait parameters improved over time for both DSA and PL with no inter-group differences, whereas DSA, regarding hip rotation range of motion, showed lower values at T3 and T1 compared with PRE and, furthermore, this group had lower values at T1 and T3 compared with PL. All foregoing comparisons are statistically signficant (p < 0.05)Interpretation - DSA showed longer surgical time and lower blood loss compared with PL and early improvements in TUG, spatiotemporal, and kinematic gait parameters, highlighting rapid muscle strength recovery.

Effect of High-Intensity Interval Training Versus Small-Sided Games Training on Sleep and Salivary Cortisol Level.

PURPOSE: The authors compared sleep quality and salivary cortisol concentration after high-intensity interval training (HIIT) and small-sided games (SSGs) performed at the habitual training time in nonprofessional male soccer players. METHODS: A total of 32 players (age = 24 [6] y, height = 1.77 [0.06] m, and body mass = 75 [12] kg) were randomized into an HIIT group or an SSG group. Actual sleep time, sleep efficiency (SE), sleep latency, immobility time (IT), moving time (MT), and fragmentation index were monitored using actigraphy before (PRE) and 2 nights after (POST 1 and POST 2) the training session. Salivary cortisol levels were measured before (PRE) and after (POST) training. Cortisol awakening response was evaluated. RESULTS: Significant intragroup differences in the HIIT group were noted for actual sleep time (P < .0001), SE (P < .0001), sleep latency (P = .047), IT (P < .0001), MT (P < .0001), and fragmentation index (P < .0001) between PRE and POST 1 and for SE (P = .035), IT (P = .004), MT (P = .006), and fragmentation index (P = .048) between PRE and POST 2. Intergroup differences for actual sleep time (P = .014), SE (P = .048), IT (P < .0001), and MT (P = .046) were observed between the HIIT and the SSGs group at POST 1 were detected. Significant intragroup variations were observed in PRE and POST salivary cortisol levels (P < .0001 for HIIT; P = .0003 for SSGs) and cortisol awakening response (P < .0001 for HIIT; P < .0001 for SSGs). Significant intergroup differences between the HIIT and the SSGs group were found at POST (P < .0001) and in cortisol awakening response (P = .017). CONCLUSIONS: Changes in actigraphy-based sleep parameters and salivary cortisol levels were greater after an acute session of HIIT than SSGs in this sample of nonprofessional male soccer players.

Exploring circannual rhythms and chronotype effect in patients with Obsessive-Compulsive Tic Disorder (OCTD): A pilot study.

BACKGROUND: The aim of this study was to test, through a chronobiologic approach, the existence of a significant circannual rhythm of tics and obsessive-compulsive symptoms in patients with Obsessive-Compulsive Tic Disorder (OCTD). The chronotype effect on tics and OC symptoms during seasons was also studied. METHODS: Patients with a diagnosis of OCTD (N = 37; mean age = 18.78 ± 8.61) underwent four clinical evaluations: Winter (WIN), Spring (SPR), Summer (SUM) and Autumn (AUT). Tics were evaluated through Yale Global Tic Severity Scale (YGTSS) and OC symptoms through Yale-Brown Obsessive Compulsive Scale (Y-BOCS). Patients' chronotype was assessed by the Horne-Ostberg morningness-eveningness questionnaire (MEQ), which categorizes subjects according to the individuals'chronotype, being morning-type, evening-type, and neither-type. RESULTS: A statistically significant circannual rhythm was observed for OC symptoms (p = 0.007), with the acrophase occurring between AUT and WIN. Y-BOCS differed along the year (p = 0.0003 and η2p = 0.40) with lower results in SUM compared to WIN (p < 0.05) and AUT (p < 0.01). Tics displayed no circannual rhythm and YGTSS scores were comparable among seasons. Patients were classified as 15 morning-types (40.5%) 15 neither-types (40.5%) and 7 evening-types (19.0%). YGTSS data were similar for all chronotypes while Y-BOCS results were greater during SUM in evening-types than morning-type patients (p < 0.05; 15.7 ± 5.2 vs 3.4 ± 6.0). LIMITATIONS: It is essential to investigate the existence of tics and OC symptoms circannual rhythms over the course of more than one year with a larger sample. CONCLUSIONS: OC symptoms displayed a significant circannual rhythm and were influenced by patients' chronotype. On the contrary, tics resulted similar among seasons and chronotypes.

Acute sleep hygiene strategy improves objective sleep latency following a late-evening soccer-specific training session: A randomized controlled trial.

The aim of this study was to evaluate the effects of sleep hygiene (SH) education on sleep quality in soccer players after a late-evening small-sided-game (SSG) training session. Twenty-nine non-professional players were recruited and allocated to either an experimental group (EG, n = 17) that received SH education, or a control group (CG, n = 12). SSG consisted of 3 × 4 min in a 4vs4, with 3 min of recovery and was performed at 8.00 p.m. Sleep quality was monitored via actigraphy and sleep diary entries before (PRE) and two nights after (POST1, POST2) the SSG. Sleep latency (SL) differed between the two groups at POST1 (4.9 ± 5.4 vs. 15.5 ± 16.1 for EG and CG, respectively; p = 0.017, effect size [ES] = 2.0); SL values were lower at POST1 compared to PRE for the EG (-47%; p = 0.021, ES = 0.6). Subjective sleep quality was better in the EG than the CG at POST1 (8.6 ± 1.0 vs. 7.1 ± 2.0 for EG and CG, respectively; p = 0.016, ES = 0.9) with a significant improvement over PRE-values (+11.0%, p = 0.004, ES = 0.8). Although SL and subjective sleep quality did not decrease significantly from POST1 to POST2 values at POST2 no longer differed significantly form baseline and, hence, indicate that observed effects may be short-lasting. No other objective sleep indices were influenced by late-evening training or SH practices implemented by the EG. Soccer players may benefit from acute SH strategies to reduce the time to sleep onset after late-evening training sessions.

Simultaneous bilateral unicompartmental knee replacement improves gait parameters in patients with bilateral knee osteoarthritis.

BACKGROUND: Unicompartmental knee replacement (UKR) can provide reliable clinical and functional outcomes when performed simultaneously in both knees for treating bilateral osteoarthritis (OA). No studies to date have evaluated gait pattern after simultaneous bilateral UKR. The aim of this study was to evaluate changes in gait variables after bilateral single-stage UKR (B-UKR) and to compare them with the outcomes after unilateral UKR in two other groups of patients: one with bilateral knee OA (P-UKR) and one with the contralateral knee unaffected (H-UKR). METHODS: Three-dimensional motion cohort data were prospectively collected before and six months after surgery; 37 were allocated to the B-UKR (n = 13), P-UKR (n = 12) or H-UKR (n = 12) group. Spatiotemporal variables (stride length, gait speed, gait cadence, stance phase, swing phase, and double support phase) and kinematic parameters (knee flexion and extension peak values, knee range of motion (ROM), and hip abduction peak value) were analyzed using mixed analysis of variance (ANOVA). The magnitude of effect for significant outcomes (ES) was determined using Cohen's d. RESULTS: Postoperative improvement in gait cadence (P < 0.01; ES = 1.20), walking speed (P < 0.05; ES = 0.58), stride length (P < 0.05; ES = 0.67), knee ROM (P < 0.05; ES = 0.89), knee flexion (P < 0.05; ES = 0.94), and hip abduction (P < 0.001; ES = 1.16) was noted for the B-UKR group, whereas only stride length improved (P < 0.05; ES = 0.48) for the H-UKR group, and no changes in any gait parameter were seen for the P-UKR group. CONCLUSIONS: Postoperative improvement in gait parameters was observed in the B-UKR patients with bilateral OA. Whenever possible, simultaneous bilateral UKR should be considered in such patients.

The Role of the Molecular Clock in Promoting Skeletal Muscle Growth and Protecting against Sarcopenia.

The circadian clock has a critical role in many physiological functions of skeletal muscle and is essential to fully understand the precise underlying mechanisms involved in these complex interactions. The importance of circadian expression for structure, function and metabolism of skeletal muscle is clear when observing the muscle phenotype in models of molecular clock disruption. Presently, the maintenance of circadian rhythms is emerging as an important new factor in human health, with disruptions linked to ageing, as well as to the development of many chronic diseases, including sarcopenia. Therefore, the aim of this review is to present the latest findings demonstrating how circadian rhythms in skeletal muscle are important for maintenance of the cellular physiology, metabolism and function of skeletal muscle. Moreover, we will present the current knowledge about the tissue-specific functions of the molecular clock in skeletal muscle.

Actigraphy-based Sleep Parameters and Rest-activity Circadian Rhythm in a Young Scoliotic Patient Treated with Rigid Bracing: A Case Study.

The correct expression of circadian rhythmicity, together with a good sleep behavior, are key factors for the body homeostasis. Rest-activity circadian rhythms (RARs) are involved in the control of the sleep-wake cycle and altered RARs could lead to a compromised health status. Therefore, we aimed to investigate the existence of RAR and to study actigraphy-based sleep behavior in a 14-year-old male patient affected by severe idiopathic scoliosis and treated with a rigid brace 23 hours per day. RAR and sleep parameters were studied through actigraphy for seven consecutive days in July 2018. The mean cosinor analysis revealed the presence of a significant RAR (p < 0.001), specifically: the percentage of rhythm was 23.4%, the mean MESOR was 84.6 Activity Count (AC), the amplitude registered a mean value of 74.4 AC's, and the acrophase occurred at 17:56 h. The subject reached a good sleep quantity: 507.9 ± 30.2 minutes of Time in Bed with a mean Total Sleep Time of 450.7 ± 20.1 minutes; Similarly, Sleep Efficiency was equal to 83.3 ± 7.2% and the Fragmentation Index was 27.3 ± 12.8%. We observed that both RAR and sleep behavior had normal trends in a 14-year-old patient treated with a rigid brace for a severe adolescent idiopathic scoliosis (AIS). Improved assessment of sleep in routine clinical practice can help to identify and manage health-related problems that could potentially affect some clinical outcomes, such as pain, mood state, and recovery process.

Effect of a Night Game on Actigraphy-Based Sleep Quality and Perceived Recovery in Top-Level Volleyball Athletes.

PURPOSE: To evaluate actigraphy-based sleep quality and perceived recovery before and after a night game in top-level volleyball athletes. METHODS: Data on sleep parameters were collected by actigraphy for 3 consecutive nights with 24 elite athletes (12 male and 12 female; mean age [SD] = 26.0 [3.4] y, age range = 20-33 y) during the competitive season 2016-17. Data from 1 night before and 2 nights after an official night match were studied, and athletes' subjective perception of recovery was evaluated by the Total Quality Recovery scale. The following actigraphic parameters were studied: time in bed, sleep latency, sleep efficiency, wake after sleep onset, total sleep time, immobility time, moving time, and fragmentation index. RESULTS: The analysis highlighted significant differences for all sleep variables. Total sleep time was lower the first night after the match compared with prematch sleep (P = .02) and the second night (P = .0009) after night competition (P = .0001, F2,23 = 22.93, ηp2 = .66 ). Similarly, sleep efficiency was lower immediately after the night competition compared with both prematch values (P = .03) and the second night (P = .0003) after competition (P = .0005, F2,23 = 8.93, ηp2 = .44 ). The same differences were observed in the perceived recovery values (P = .001, F2,23 = 13.37, ηp2 = .54 ). CONCLUSIONS: Coaches and medical staff should use these findings to develop a greater knowledge of how sleep differs during different phases of competition and to implement behavioral and sleep-hygiene strategies in top-level athletes.

Level- and sport-specific Star Excursion Balance Test performance in female volleyball players.

BACKGROUND: Investigations of Star Excursion Balance Test (SEBT) performance differences between competition levels and sports are limited and results are inconsistent. The aim of the present study are: 1) to compare SEBT performance between elite and semi-professional female volleyball players; 2) to evaluate differences in SEBT scores between positions (Hitters, Middle Blockers, Setters, and Liberoes); and 3) to compare dynamic balance characteristics between professional female Italian volleyball players with NCAA Division I female athletes practicing six different sports (hockey, football, basketball, golf, softball, and volleyball). For the latter comparison, previously published data obtained from a study were used. METHODS: Fifty-one female volleyball players were grouped in two groups, elite athletes (EG; N.=27) and semi-professional players (SG; N.=24), and further categorized into hitters, middle blockers, setters, and liberos. Anterior (A), posteromedial (PM), and posterolateral (PL) distances, and composite score (COMP) of SEBT short form were studied. COMP was calculated as the average of the normalized distances across the three directions. RESULTS: Significant differences were observed for the A (right, P=0.014 and left, P=0.011), PL (right, P=0.017 and left, P=0.008), PM (P<0.001) directions, and COMP scores (right, P=0.008 and left, P=0.009), with higher normalized distances noted for the EG and no differences between different positions. COMP scores were lower for the EG than the NCAA Division I female hockey (P<0.001) and football players (P=0.031) but similar to those of basketball, golf, softball, and volleyball players. CONCLUSIONS: The EG scored higher on dynamic postural-control tasks than the SG. SEBT performance varied significantly between sports. Clinicians and strength coaches need to be aware of sport specific differences in dynamic postural control measurements in both rehabilitation and athletic development.