A Delayed Evening Meal Enhances Sleep Quality in Young Rugby Players.

The aim of this study was to examine the effect of delayed evening mealtime on sleep quality in young athletes. Twelve rugby players (age 15.8 ± 0.7 years) participated in a crossover within-participant design. Adolescents spent five consecutive days in each of two conditions, separated by a 2-week washout period: routine dinner (3.5 hr before bedtime) and late dinner (LD, 1.5 hr before bedtime). Other mealtimes as well as bedtime and wake-up time were usual and remained the same in both conditions. Their schedules, dietary intakes, and physical activity were controlled and kept constant throughout the study. Sleep was assessed using polysomnography on the first and the last nights in the individual rooms of the boarding school. An increase in total sleep time by 24 min (p = .001, d = 1.24) and sleep efficiency by 4.8% was obtained during LD (p = .001, d = 1.24). Improvement in sleep efficiency was mainly due to a lower wake after sleep onset (-25 min, p = .014, d = -3.20), a decrease of microarousals (-25%, p = .049, d = -0.64), and awakenings ≥90 s (-30%, p < .01, d = -0.97) in LD compared to routine dinner. There were no significant differences in sleep architecture except for a shorter slow-wave sleep (N3) latency (-6.9 min, p = .03, d = -0.778) obtained during LD. In this study, evening dinner 1.5 hr before bedtime leads to better quality and less fragmented sleep compared to evening dinner 3.5 hr before bedtime in young athletes.

Acute effect of an intensified exercise program on subsequent sleep, dietary intake, and performance in junior rugby players.

The effect of exercise on sleep remains controversial in athletes especially in junior athletes. This study tested the acute effect of additional intense rugby training on sleep, next-day dietary intake, and physical performances in adolescent rugby players compared to a day with regular exercise. 17 male rugby players in the national under-17 category (age: 15.7 ± 1.1 years, height: 1.78 ± 0.1 m, weight: 84.4 ± 13.6 kg, BMI: 26.6 ± 3.8 kg/m2, fat mass: 14.5 ± 3.4%, VO2max Yo-Yo test: 52.1 ± 4.4 mL/min/kg, evening chronotype) took part in this study. The athletes completed two 36-h experimental sessions in random order: a regular exercise program (REP) vs. an intensified exercise program (IEP) at a 1-week interval. Physical activity and sleep data were collected using accelerometers. Performance tests were conducted the next morning after an ad libitum breakfast. Sleep improved during intensive training (TST: + 26 min, SL: - 4%, WASO: - 39%, SE: + 8.5%) with moderate effect size. There was no next-day difference in calorie intake from breakfast, but macronutrient composition shifted toward proteins (regular: 15.4 ± 6.1% vs. intensive: 18.9 ± 7.4%, ES = - 0.650 [- 1.13; - 0.18]). There were no significant differences in Wingate test performance or spatial awareness task time. However, performance in submaximal tests improved. Acute intensified training results in increased sleep duration and quality without disturbing next-day performance or dietary intake in young rugby players.

Association between Low Energy Availability (LEA) and Impaired Sleep Quality in Young Rugby Players.

Low energy availability (LEA) has been associated with several physiological consequences, but its impact on sleep has not been sufficiently investigated, especially in the context of young athletes. This study examined the potential association between energy availability (EA) status and objective sleep quality in 42 male rugby players (mean age: 16.2 ± 0.8 years) during a 7-day follow-up with fixed sleep schedules in the midst of an intensive training phase. Participants' energy intake was weighed and recorded. Exercise expenditure was estimated using accelerometry. Portable polysomnography devices captured sleep on the last night of the follow-up. Mean EA was 29.3 ± 9.14 kcal·kg FFM-1·day-1, with 47.6% of athletes presenting LEA, 35.7% Reduced Energy Availability (REA), and 16.7% Optimal Energy Availability (OEA). Lower sleep efficiency (SE) and N3 stage proportion, along with higher wake after sleep onset (WASO), were found in participants with LEA compared to those with OEA (p = 0.04, p = 0.03 and p = 0.005, respectively, with large effect sizes). Segmented regression models of the EA-sleep outcomes (SE, sleep onset latency [SOL]), WASO and N3) relationships displayed two separate linear regions and produced a best fit with a breakpoint between 21-33 kcal·kg FFM-1·day-1. Below these thresholds, sleep quality declines considerably. It is imperative for athletic administrators, nutritionists, and coaches to conscientiously consider the potential impact of LEA on young athletes' sleep, especially during periods of heavy training.

Is it wiser to train in the afternoon or the early evening to sleep better? The role of chronotype in young adolescent athletes.

STUDY OBJECTIVES: To examine the effect of the timing of high-intensity exercise (afternoon vs. evening) on adolescent athletes' bedtime psychological state, sleep quality, sleep staging, and next-day wellness/sleepiness according to chronotype. METHODS: Forty-two young athletes (morning type: n = 12, intermediate type: n = 14; evening type: n = 16) completed a randomized crossover study under free-living conditions. The counterbalanced sessions include: (AEX) afternoon (1:00-3:00 p.m.) and (EEX) evening (5:30-7:30 p.m.) high-intensity exercise. Sessions were conducted over three days each and were separated by a 1-week washout period. The time in bed was fixed (10:30 p.m.-7:30 a.m.). Sleep was assessed through ambulatory polysomnography. RESULTS: The effect of high-intensity exercise on sleep differs significantly depending on the time of exercise with lower sleep efficiency: SE (-1.50%, p < .01), and higher SOL (+4.60 min, p ≤=< .01), during EEX vs. AEX. Contrary to the previous view, we discovered differences in the mediated response based on the chronotype of young athletes. These differences were observable in the psychological state at bedtime, objective sleep, and the next day's self-reported wellness. Whereas the sleep of participants with a late chronotype remains stable regardless of the time of exercise, those with an early chronotype experience higher mood disturbances and clinically significant sleep disruptions following evening high-intensity exercise. CONCLUSIONS: Exercise timing and chronotype affect the psychological state at bedtime and objective sleep in adolescent athletes. This also alters next morning signs of pre-fatigue and wellness which suggest that the consideration of both features is important to adolescent athletes' recovery.

Sleep pattern and staging in elite adolescent rugby players during the in-season competitive phase compared to an age matched non-athlete population.

Young athletes must contend with the constraints of elite sports on top of school commitments and the physiological processes associated with adolescence. This study assessed week and weekend sleep and schedule of activities in elite adolescent rugby players during the in-season competitive phase compared with age-matched non-athlete controls. 32 adolescents (GR: 16 elite rugby players, GC: 16 controls) from the same boarding school filled out a daily schedule of activities and a sleep diary, and wore a multichannel electroencephalogram for 14 days. They later filled out questionnaires on their sleep quality, sleepiness, and perceived stress. Both groups showed insufficient sleep duration during the week (<7 h). Only GC caught up on their sleep debt during the weekend (increased TIB, TST and time spent in REM sleep, all p < 0.001). Weekend TIB, TST and, N3 sleep remained similar to that for weekdays in GR. However, GR experienced lower sleep quality (decreased SE, increased WASO, all p < 0.01) and a decrease in REM sleep (p < 0.01). Schedules of activities showed an increase in time spent on overall activities during the weekend, mainly due to competition and sport-specific travel, which resulted in a decrease in sleep opportunity time compared with GC (p < 0.001). Δ sleep opportunity time (weekend-week) was associated with Δ TST (weekend-week), and Δ TST (weekend-week) was associated with sleepiness and perceived stress. Busy schedules during the competitive season decreased sleep opportunity time and prevented elite adolescent rugby players from catching up on their sleep at weekends.HIGHLIGHTSAdolescent rugby players have insufficient sleep during both week and weekend of the in-season competitive phaseCongested schedule prevented elite adolescent rugby players from catching up on their sleep at weekends.Sleep considerations are necessary when planning the weekend sporting schedules.

Randomized Double-Blind Controlled Trial on the Effect of Proteins with Different Tryptophan/Large Neutral Amino Acid Ratios on Sleep in Adolescents: The PROTMORPHEUS Study.

Disturbed sleep is common in adolescents. Ingested nutrients help regulate the internal clock and influence sleep quality. The purpose of this clinical trial is to assess the effect of protein tryptophan (Trp)/large neutral amino acids (LNAAs) ratio on sleep and circadian rhythm. Ingested Trp is involved in the regulation of the sleep/wake cycle and improvement of sleep quality. Since Trp transport through the blood-brain barrier is competing with LNAAs, protein with higher Trp/LNAAs were expected to increase sleep efficiency. This randomized double-blind controlled trial will enroll two samples of male adolescents predisposed to sleep disturbances: elite rugby players (n = 24) and youths with obesity (n = 24). They will take part randomly in three sessions each held over a week. They will undergo a washout period, when dietary intake will be calibrated (three days), followed by an intervention period (three days), when their diet will be supplemented with three proteins with different Trp/LNAAs ratios. Physical, cognitive, dietary intake, appetite, and sleepiness evaluations will be made on the last day of each session. The primary outcome is sleep efficiency measured through in-home electroencephalogram recordings. Secondary outcomes include sleep staging, circadian phase, and sleep-, food intake-, metabolism-, and inflammation-related biochemical markers. A fuller understanding of the effect of protein Trp/LNAAs ratio on sleep could help in developing nutritional strategies addressing sleep disturbances.

Hemorheological disturbances in the overtraining syndrome.

Contemporary sports imply huge training volumes, with thus an increasing danger of overloading. The timely detection of the state of overloading in the organism as a whole or in skeletal muscles presents a difficult and complicated problem. A standardized questionnaire has been proposed by the French consensus group on overtraining of the Société Française de Médecine du Sport (SFMS) and allows the calculation of a "score" that may help to quantify the early clinical symptoms of the overtraining syndrome in sportsmen submitted to a heavy training program. We previously reported that this overtraining score is correlated with blood viscosity due to a correlation of this score with plasma viscosity and hematocrit. When subjects with a high score were compared to subjects with a lower score they appeared to have a higher blood viscosity at native (but not corrected) hematocrit, explained by higher values in both plasma viscosity and hematocrit. By contrast, there was no difference in RBC deformability and aggregation. Therefore, the early signs of overtraining in elite sportsmen are associated with a hemorheologic pattern that suggests some degree of reversal of the "autohemodilution" which characterizes fitness. In a further study we reported that the feeling of heavy legs in overtrained athletes is related to impaired hemorheology. Although well matched with controls for age and body composition, subjects with a complaint of heavy legs had higher plasma viscosity and a higher red cell aggregation as measured with laser backscattering. These findings suggest that the feeling of heavy legs in overtrained athletes are related to hemorheologic disturbances. In the light of the recent concept explaining this syndrome by a mild chronic inflammatory reaction, the investigation of hemorheology in overtraining can be a promising area for hemorheologists, providing both markers and likely pathophysiological explanations for some symptoms of this situation.

Lipids and theirs carriers in sportsmen: the lipoprotein particles.

This study presents an original approach to the effect of regular sporting activity on the metabolism of lipids. We have examined the physiological variations of lipoparticles (Lp) AI, Lp B:CIII, Lp B:E, Lp (a) and the principal lipid markers in 21 high-level rugby players and men of the same age group who take part in no sporting activity (reference group; n = 35). The analysis showed a paradoxical decrease in the high-density lipoprotein fraction of cholesterol (P < 0.05) and in apolipoprotein AI (P < 0.0001), and an increase in the apoprotein B/apoprotein AI ratio in the sportsmen, compared with the reference group. According to these results, physical activity seems to have only a slight influence on anti-atherogenic serum markers. However, the drop in Lp B:E (P < 0.0001) and the static level of Lp AI in the sportsmen indicate a favourable effect of sport on these lipoparticles. The results of this study also highlight the importance of triglycerides and their metabolism. In fact, the lower triglyceride levels (P < 0.05) of the sportsmen justify special attention to diet, especially during a period of competition.