Effects of a nighttime melatonin ingestion on dynamic postural balance and muscle strength the following morning in people living with multiple sclerosis: A preliminary study

BACKGROUND

Decreased endogenous melatonin concentrations in people with multiple sclerosis (PwMS) are associated with fatigue and pain that impair postural balance and muscle strength. Melatonin ingestion had analgesic and anti-fatigue effects. However, the acute effect of exogenous melatonin on dynamic postural stability and muscle strength has not been studied yet in PwMS. This study aimed to investigate the safety and the efficacy of a nighttime melatonin intake on dynamic postural balance and lower-extremity muscle strength the following morning in PwMS.

METHODS

Fourteen PwMS (28.36 ± 6.81 years) were assessed (8 a.m.) pre- and post-acute intake of melatonin or placebo (6mg, 30 minutes before nocturnal bedtime). Evaluated parameters included dynamic postural balance (force platform), lower-extremity muscle strength [Five-Repetition Sit-To-Stand Test (5-STST)], hand dexterity (Nine-Hole Peg Test), nociceptive pain [Visual Analogue Scale (VAS)], neuropathic pain [Neuropathic Pain 4 Questions (DN4)], sleep quality and fatigue perception [Hooper Index (HI)].

RESULTS

In the frontal plane, melatonin reduced the center of pressure (CoP) path length (CoPL), CoPL in the anteroposterior axis (CoPLY) and CoP sway area (CoPAr) compared with placebo by 7.56% (p=0.02, Cohens'd (d)=1.24), 19.27% (p<0.001, d=2.60) and 13.82% (p<0.001, d=2.02), respectively. Melatonin induced a higher decrease in these posturographic parameters compared with placebo in the sagittal plane [CoPL: 9.10% (p=0.005, d=1.02), CoPLY: 4.29% (p=0.025, d=1.07) and CoPAr: 7.45% (p=0.038, d=0.74)]. Melatonin decreased 5-STST duration as well as VAS, DN4, HI-fatigue and HI-sleep scores compared with placebo by 8.19% (p=0.008, d=1.19), 5.74% (p=0.04, d=0.82), 27.30% (p=0.023, d=0.98), 40.15% (p=0.044, d=0.85) and 30.16% (p=0.012, d=1.10), respectively.

CONCLUSION

This preliminary study, among PwMS, showed that acute melatonin ingestion was safe and efficient for improving dynamic postural stability and lower-extremity muscle strength probably through its analgesic and anti-fatigue effects.

Nocturnal Melatonin Ingestion Improves Soccer Players' Short-Term Maximal Performances on the Following Day

Purpose: Exogenous melatonin has been proven to have beneficial effects on sleep. A good sleep quality promotes recovery and improves physical performance. In this sense, the present study aimed to explore the potential effect of nocturnal melatonin ingestion on psycho-cognitive and short-term maximal performances, in the following morning. Method: Twelve professional soccer players (22.9 ± 1.3 years, 1.80 ± 0.05 m, and 72.0 ± 8.8 kg) volunteered to perform two separate testing sessions after either nocturnal melatonin or placebo ingestion. The next morning, participants performed the following psycho-cognitive and physical tests: Hooper's index, reaction time, vigilance, handgrip strength (HG), squat jump (SJ), modified agility T-test (MAT) and Wingate anaerobic test (WanT). Rating of perceived exertion (RPE) and blood lactate [La] were recorded, respectively, immediately and 3 min after the WanT. Blood glucose [GL] was measured before and 3 min after WanT. Results: Compared with placebo, melatonin improved subjective sleep quality, short-term maximal performances (HG and SJ), reaction-time, as well as peak and mean WanT powers and decreased fatigue index and RPE scores. However, [La] and [GL] were not affected by melatonin ingestion. Conclusion: Nocturnal melatonin intake before sleep has beneficial effects on cognitive and physical performances the following day.

Sensor-Based Assessment of Time-of-Day-Dependent Physiological Responses and Physical Performances during a Walking Football Match in Higher-Weight Men

Monitoring key physiological metrics, including heart rate and heart rate variability, has been shown to be of value in exercise science, disease management, and overall health. The purpose of this study was to investigate the diurnal variation of physiological responses and physical performances using digital biomarkers as a precise measurement tool during a walking football match (WFM) in higher-weight men. Nineteen males (mean age: 42.53 ± 12.18 years; BMI: 33.31 ± 4.31 kg·m-2) were engaged in a WFM at two different times of the day. Comprehensive evaluations of physiological parameters (e.g., cardiac autonomic function, lactate, glycemia, and oxygen saturation), along with physical performance, were assessed before, during, and after the match. Overall, there was a significant interaction (time of day x WFM) for mean blood pressure (MBP) (p = 0.007) and glycemia (p = 0.039). Glycemia decreased exclusively in the evening after WFM (p = 0.001), while mean blood pressure did not significantly change. Rating of perceived exertion was significantly higher in the evening than in the morning (p = 0.04), while the heart rate recovery after 1 min (HRR60s) of the match was lower in the evening than in the morning (p = 0.048). Overall, walking football practice seems to be safe, whatever the time of day. Furthermore, HRR60, glycemia, and (MBP) values were lower in the evening compared to the morning, suggesting that evening exercise practice could be safer for individuals with higher weight. The utilization of digital biomarkers for monitoring health status during WFM has been shown to be efficient.

Is moderate-intensity interval training more tolerable than high-intensity interval training in adults with obesity?

Interval training (IT) has been shown to be a time-effective alternative to traditional training programmes in the management of obesity. Nevertheless, studies comparing the effects of different IT intensities on inflammation, muscle and liver damage, and perceptual responses in people with obesity are relatively scarce. This study aimed to compare the acute effects of two different IT protocols matched by the mean load and duration on biochemical and perceptual responses in sedentary adults with obesity. Twenty-two volunteers (age = 33.40 ± 10.01 years, BMI = 38.29 ± 7.09 kg/m²) were randomized to perform two conditions: moderate-intensity IT (MIIT) 5 × 3 min (70% of peak power output (PPO))/2 min (45%PPO) and high-intensity IT (HIIT) 8 × 1 min (90%PPO)/2 min (45%PPO). Blood samples were drawn before and after exercise for biochemical and haematological measurements. Rating of perceived exertion (RPE) was assessed during and after exercise. Perceptual pain was evaluated before, throughout and after exercise. C-reactive protein, white blood cells and neutrophils increased only after HIIT (p < 0.001, for all). Aspartate aminotransferase, alanine aminotransferase, creatine kinase and lactate dehydrogenase increased in both HIIT and MIIT (p < 0.001, for all), without any difference between sessions. HIIT induced a greater increase of blood lactate compared to MIIT (p < 0.05). Pain and RPE scores were higher during HIIT vs. MIIT (p < 0.001 and p < 0.01, respectively). MIIT induced fewer immune system perturbations and less muscle pain and was perceived as more tolerable compared to HIIT session. Therefore, MIIT could be used as a first step to promote body adaptations before starting a HIIT programme in sedentary people with obesity.

Melatonin Ingestion Prevents Liver Damage and Improves Biomarkers of Renal Function Following a Maximal Exercise

Background: While the promotion of the beneficial effects of melatonin (MEL) ingestion on the modulation of oxidative stress is widespread, less attention is given to the biological influence that it could exert on the results of hematology and clinical chemistry parameters. This study was undertaken to assess the effects of acute MEL ingestion on these parameters during a maximal running exercise. Methods: In double blind randomized design, 12 professional soccer players [age: 17.54 ± 0.78 yrs, body mass: 70.31 ± 3.86 kg, body height: 1.8 ± 0.08 m; maximal aerobic speed (MAS): 16.85 ± 0.63 km/h; mean ± standard deviation], all males, performed a diurnal (17:00 h ± 30 h) running exercise test (RET) at 100% of their MAS following either MEL or placebo ingestion. Blood samples were obtained at rest and following the RET. Results: Compared to placebo, MEL intake decreased post-exercise biomarkers of liver damage (aspartate aminotransferase, p<0.001; alanine aminotransferase, p<0.001; gamma-glutamyltransferase; p<0.05) and improved post-exercise renal function markers (i.e., creatinine, p<0.001). However, lipid profile, glucose, lactate and leukocyte were not affected by MEL ingestion. Regarding the time to exhaustion, no difference was found between MEL (362.46 ± 42.06 s) and PLA (374.54 ± 57.97 s) conditions. Conclusion: The results of this investigation clearly attest that MEL ingestion before a maximal running exercise might protect athletes from liver damage and perturbation in renal function biomarkers. However, this study comprises an acute MEL supplementation and no assessment on chronic effects or circadian rhythm the day before was done.

Intervention Based on Psychomotor Rehabilitation in Children with Autism Spectrum Disorder ASD: Effect on Postural Control and Sensory Integration

Postural stability and control are essential motor skills for successfully performing various activities of daily living. However, children with autism spectrum disorder (ASD) exhibit significant sensorimotor impairments. The aim of this study was to investigate the efficacy of psychomotricity training on postural control (PC) of children with ASD. We recruited thirty children (age = 8.01 ± 1.2; weight = 31.66 ± 8.1 kg; height = 129.7 ± 10.8 cm) diagnosed with ASD (intellectual quotient > 50) to participate in this study. They were divided into two groups: the experimental group (n = 16) and control group (n = 14). Children in the experimental group were trained with psychomotor activities two times a week for nine weeks. Statistic postural balance was assessed before and after intervention and on different vision conditions. The results showed that the psychomotor training significantly improved PC in standing position under different conditions when compared to the control group, in all parameters (CoPA; CoPLX; CoPLy) (p < 0.01). Our preliminary findings suggest the usefulness of the psychomotor training in children with ASD on static PC.

Physiological response and physical performance after 40 min and 90 min daytime nap opportunities

This study aimed to examine the impact of 40-min and 90-min naps on performance in the 5-m shuttle run test (5mSRT) and on various physiological and perceptual measures. Sixteen male athletes (20 ± 3 years, 173 ± 7 cm, 67 ± 7 kg) performed the 5mSRT after a 40-min nap (N40), after a 90-min nap (N90), and in a no-nap, control condition (N0). The 5mSRT involves six repetitions of 30 s of all-out exercise. Total distance (in the six repetitions) and highest distance (in a single repetition) in the 5mSRT were greater after naps than in N0 (p < 0.001), and the total distance, which reflects the anaerobic capacity, was greater in N90 than in N40 (p < 0.05). Physiological and perceptual responses were favourable in both nap conditions (p < 0.01), more so in N90 than in N40 (p < 0.05). Together, the results support the contention that physiological/perceptual responses after napping contribute to improved exercise performance and that longer naps are more effective.

40-min nap opportunity attenuates heart rate and perceived exertion and improves physical specific abilities in elite basketball players

The effect of a 40-min nap opportunity on physiological responses and specific abilities was investigated. Twelve high-level professional basketball players (26.33±5.2 years; 193.17±7.1 m; 87.48±11.2 kg) undertook randomly 40-min nap opportunity (NAP) and control condition (CON). Wellness (Hooper Index) and Epworth Sleepiness Scale (ESS) were measured before and after both conditions. Defensive (DA) and offensive (OA) agility and upper body power (UBP) were assessed after both conditions. Shooting skill (SST) performance was evaluated prior and after a fatiguing task (FT). Heart rate (HR) and rating of perceived exertion (RPE) were recorded during SST-test, FT and SST-retest. ESS, Hooper's stress and fatigue score were significantly lower after nap compared to those before nap (0.009 ≤ p ≤ 0.03). Better performance was obtained in NAP compared to CON condition for DA, OA and UBP (0.0005 ≤ p ≤ 0.02). SST performance was significantly higher in NAP compared to CON in the retest session (p = 0.003, Δ = 20.2%).         The improved performance was associated with significant lower HRpeak (p = 0.01, Δ = 5.25%) and RPE (p = 0.003, Δ = 15.12%). In conclusion, NAP reduced sleepiness and stress and fatigue and enhances physical outcomes of specific skills in elite basketball players.

Effectiveness of Ramadan diurnal intermittent fasting and concurrent training in the management of obesity: is the combination worth the weight?

BACKGROUND AND AIMS

We investigated, in men with obesity, the efficacy of the combination of two strategies (Ramadan diurnal intermittent fasting 'RDIF' strategy vs RDIF plus concurrent training program 'RDIF-CT' strategy) known for their positive impact on body composition and then we explored the possible impact on metabolic and inflammatory biomarkers.

METHODS AND RESULTS

Twenty obese men, age: 31.8 ± 7.05 years, BMI: 33.1 ± 4.2 kg m^-2, performing regularly RDIF, were randomized into two groups: RDIF-CT (n = 10) and RDIF without training (RDIF-NCT) (n = 10). The RDIF-CT group participated in High intensity interval training (HIIT) program combined with resistance exercises for 4 weeks. Body composition, blood glucose, lipid profile, liver biomarkers and inflammation were assessed before and after 4-week RDIF. Both groups showed a significant decrease in weight, fat mass (FM), fat percentage (Fat%) and waist circumference (WC) and an improvement in blood glucose, lipid profile and inflammation. Fat free mass decreased significantly in RDIF-NCT (p < 0.05) while remaining unchanged in RDIF-CT. However, RDIF-CT induced greater improvements in body composition (i.e., weight, FM, Fat% and WC (p < 0.05, p < 0.01, p < 0.01 and p < 0.05; respectively)) as well as greater decrease in lipid biomarkers (i.e., TC, TG and LDL (p < 0.01 for all)), inflammation (i.e., CRP (p < 0.05)), and liver damage (i.e., ASAT, ALAT and Gamma-GT (p < 0.01, p < 0.05 and p < 0.001; respectively)) compared to RDIF-NCT group pre-post intervention.

CONCLUSIONS

Our results suggest that a combination of RDIF and CT induces greater changes in body composition, lipid profile, inflammation and liver biomarkers compared to RDIF strategy alone.

CLINICAL TRIAL REGISTER

PACTR202203475387226.

Dietary Intake and Body Composition During Ramadan in Athletes: A Systematic Review and Meta-Analysis With Meta-Regression

The aim of this research was to evaluate the effect of Ramadan observance on dietary intake and body composition in adult athletes. This was a systematic review and meta-analysis. Data sources used were PubMed, Web of Science, Scopus, and Taylor and Francis. Eligibility criteria for selecting studies were as follows: single-group, pre-/post-Ramadan, with or without control group, conducted in athletes aged ≥19 years training at least twice a week, and published in any language before August 25, 2021. Studies assessing dietary intake and/or body composition were deemed eligible. The methodological quality of studies was assessed using QualSyst. Nine studies evaluated dietary intake; 4 of these were rated as strong quality and the remaining as moderate. Of the 17 selected studies evaluating body composition, 7 were of strong quality and the remaining 10 were rated as moderate. Compared to pre-Ramadan, energy (number of studies, K = 7; number of participants, N = 78; g = -0.781; 95% confidence interval [CI], -1.416 to -0.145; p = 0.016), carbohydrate (K = 5; N = 50; g = -1.643; 95% CI, -2.949 to -0.336; p = 0.014), and water (K = 4; N = 39; g = -1.081; 95% CI, -1.371 to -0.790; p = 0.000) intakes decreased during Ramadan. However, fat (K = 5; N = 50; g = -0.472; 95% CI, -1.085 to 0.140; p = 0.131) and protein (K = 5; N = 60; g = -0.574; 95% CI, -1.213 to -0.066; p = 0.079) intakes remained unchanged. Compared to pre-Ramadan, body mass (K = 16; N = 131; g = -0.262; 95% CI, -0.427 to -0.097; p = 0.002) and body fat percentage (K = 8; N = 81; g = -0.197; 95% CI, -0.355 to -0.040; p = 0.014) decreased in the fourth week of Ramadan. Lean body mass did not change during Ramadan (K = 4; N = 45; g = -0.047; 95% CI, -0.257 to 0.162; p = 0.658). Carbohydrate and total water intake decreased with the observance of Ramadan, but fat and protein intake were unchanged. Continued training of athletes during Ramadan was associated with a decreased body mass and body fat percentage, but not lean body mass, toward the end of the fasting month. Key pointsRamadan fasting decreases body mass and body fat percentage of athletes, but not lean body mass.Longer durations of fasting could provoke more pronounced decrements in body mass.Carbohydrate and total water intake decreased during Ramadan in athletes.Future studies, with greater methodological rigor, are required to better discern changes in dietary intake and body composition during Ramadan. Supplemental data for this article is available online at https://doi.org/10.1080/07315724.2021.2000902 .

Benefits and risks of napping in older adults: A systematic review

A growing body of evidence indicates that napping is common among older adults. However, a systematic review on the effect of napping on the elderly is lacking. The aim of this systematic review was to (i) determine how studies evaluated napping behavior in older adults (frequency, duration and timing); (ii) explore how napping impacts perceptual measures, cognitive and psychomotor performance, night-time sleep and physiological parameters in the elderly (PROSPERO CRD42022299805). A total of 738 records were screened by two researchers using the PICOS criteria. Fifteen studies met our inclusion criteria with a mean age ranging from 60.8 to 78.3 years and a cumulative sample size of n = 326. Daytime napping had an overall positive impact on subjective measures (i.e., sleepiness and fatigue), psychomotor performances (i.e., speed and accuracy) and learning abilities (i.e., declarative and motor learning). Additionally, studies showed (i) consistency between nap and control conditions regarding sleep duration, efficiency and latency, and proportion of sleep stages, and (ii) increase of 24 h sleep duration with nap compared to control condition. Based on the findings of the present review, there is minimal evidence to indicate that napping is detrimental for older adults' nighttime sleep. Future studies should consider involving repeated naps during a micro-cycle in order to investigate the chronic effect of napping on older adults.

Melatonin supplementation alleviates cellular damage and physical performance decline induced by an intensive training period in professional soccer players

Melatonin has been proved to have positive effects on cellular damage and metabolic regulation. The aim of the study was to determine the effect of melatonin supplementation during an intensive training period on physical performance decline, oxidative stress and cellular damage state. The investigation was conducted on 20 soccer players who participated in an exhaustive six-day training schedule associated with daily 5 mg oral melatonin or placebo ingestion. Resting blood samples and physical performance were measured before and after the training period. The mixed 2-way ANOVA (group x training camp) showed that compared to placebo, melatonin intake prevented an increase in advanced oxidation protein products (p>0.05) and increased the antioxidant enzyme activity (i.e., superoxide dismutase; p<0.001). In addition, melatonin prevented an increase of biomarkers of renal function (e.g., creatinine; p>0.05) and biomarkers of muscle (e.g., creatine kinase; p>0.05) and liver (e.g., gamma-glutamyltransferase; p>0.05) damage. Furthermore, melatonin alleviated the deterioration in physical performance (countermovement jump, five-jump test and 20-m sprint; p>0.05). In conclusion, the obtained data showed increased oxidative stress and renal, muscle and liver damage in professional soccer players during an exhaustive training schedule. Melatonin intake during the training period exerts beneficial effects on physical performance and protects tissues against the deleterious effects of reactive oxygen species and cellular damage.

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.

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).

Effects of Walking Football During Ramadan Fasting on Heart Rate Variability and Physical Fitness in Healthy Middle-Aged Males

This study aimed to investigate the effect of a walking football (WF) program during Ramadan fasting (RF) on heart rate variability (HRV) indices, body composition, and physical fitness in middle-aged males. Thirty-one healthy sedentary men were randomized to WF (n = 18) and control (n = 13) groups. Both groups participated in RF. The WF group were involved in a training program (small-sided games) of three sessions a week during RF. The time and frequency domains of HRV, body composition, handgrip, lumbar strength, Modified Agility Test (MAT), and 6-minute walk test (6MWT) were measured before Ramadan (BR), during Ramadan (DR), and after Ramadan (AR). We reported that RF has significantly altered some parameters of HRV DR; the mean HR decreased while the mean RR, LF, and HF increased. WF had a significant effect on HRV and mean HR DR compared with BR and AR decreased while mean RR, HF and LF increased. DR, body mass decreased in both groups, while body mass index (BMI) decreased and lean mass increased only in WF group. Lower body mass and BMI levels were reported AR only in WF group. Physical capacity improved AR, compared with BR, only in the WF group with longer distance in 6MWT, shorter time(s) in MAT, and higher lumbar strength levels. We conclude that RF increases parasympathetic system activity. WF practice during RF is safe and might improve body composition, physical fitness, autonomic cardiac function, and physical fitness in middle-aged males.

Melatonin reduces muscle damage, inflammation and oxidative stress induced by exhaustive exercise in people with overweight/obesity

BACKGROUND

Intense physical exercise leads to inflammation, oxidative stress and muscle damage, and these responses are of greater magnitude in people with obesity. Melatonin (MLT) is considered an endogenous antioxidant which may have beneficial effects against inflammation, oxidative stress and promote tissue repair after exercise. The aim of this study was to examine the effect of MLT on inflammatory parameters, oxidative stress and muscle damage in people with overweight/obesity after a high-intensity interval exercise (HIIE).

METHODS

A total of 23 subjects with obesity (9 men and 14 women) age: 33.26 ± 9.81 years, BMI: 37.75 ± 8.87 kg.m-2 were randomized to participate in two experimental sessions: HIIE + Placebo and HIIE + MLT (3 mg). The HIIE protocol corresponds to 8 intervals of 1 min (90% of the maximal aerobic power (MAP)) alternating with 2 min recovery (45% of the MAP). Blood samples were drawn before and 5 min after each exercise session.

RESULTS

MLT ingestion attenuated the increase of inflammation (C-reactive protein, white blood cells (P < 0.001, ηp2 = 0.45; for both) and Neutrophils (P < 0.01, ηp2 = 0.36)) and hepatic and muscle damage (Aspartate aminotransferase (P < 0.01, ηp2 = 0.25), Alanine aminotransferase (P < 0.01, ηp2 = 0.27) and Creatine kinase (P = 0.02, ηp2 = 0.23). MLT also attenuated the exercise induced lipid and protein peroxidation (i.e., Malondialdehyde (P = 0.03, ηp2 = 0.19) and AOPP (P < 0.001, ηp2 = 0.55)). Concerning the antioxidant status, MLT intake increased Thiol (P < 0.01, ηp2 = 0.26) and Catalase (P < 0.01, ηp2 = 0.32) and decreased Uric acid (P = 0.02, ηp2 = 0.2) and Total bilirubin (P < 0.01, ηp2 = 0.33).

CONCLUSIONS

MLT intake before HIIE reduced muscle damage by modulating oxidative stress and preventing overexpression of the pro-inflammatory mediators in people with obesity.

COVID-19 Lockdowns: A Worldwide Survey of Circadian Rhythms and Sleep Quality in 3911 Athletes from 49 Countries, with Data-Driven Recommendations

Objective

In a convenience sample of athletes, we conducted a survey of COVID-19-mediated lockdown (termed ‘lockdown’ from this point forward) effects on: (i) circadian rhythms; (ii) sleep; (iii) eating; and (iv) training behaviors.

Methods

In total, 3911 athletes [mean age: 25.1 (range 18–61) years, 1764 female (45%), 2427 team-sport (63%) and 1442 elite (37%) athletes] from 49 countries completed a multilingual cross-sectional survey including the Pittsburgh Sleep Quality Index and Insomnia Severity Index questionnaires, alongside bespoke questions about napping, training, and nutrition behaviors.

Results

Pittsburgh Sleep Quality Index (4.3 ± 2.4 to 5.8 ± 3.1) and Insomnia Severity Index (4.8 ± 4.7 to 7.2 ± 6.4) scores increased from pre- to during lockdown (p < 0.001). Pittsburgh Sleep Quality Index was predominantly influenced by sleep-onset latency (p < 0.001; + 29.8%), sleep efficiency (p < 0.001; − 21.1%), and total sleep time (p < 0.001; − 20.1%), whilst Insomnia Severity Index was affected by sleep-onset latency (p < 0.001; + 21.4%), bedtime (p < 0.001; + 9.4%), and eating after midnight (p < 0.001; + 9.1%). During lockdown, athletes reported fewer training sessions per week (− 29.1%; d = 0.99). Athletes went to bed (+ 75 min; 5.4%; d = 1.14) and woke up (+ 150 min; 34.5%; d = 1.71) later during lockdown with an increased total sleep time (+ 48 min; 10.6%; d = 0.83). Lockdown-mediated circadian disruption had more deleterious effects on the sleep quality of individual-sport athletes compared with team-sport athletes (p < 0.001; d = 0.41), elite compared with non-elite athletes (p = 0.028; d = 0.44) and older compared with younger (p = 0.008; d = 0.46) athletes.

Conclusions

These lockdown-induced behavioral changes reduced sleep quality and increased insomnia in athletes. Data-driven and evidence-based recommendations to counter these include, but are not limited to: (i) early outdoor training; (ii) regular meal scheduling (whilst avoiding meals prior to bedtime and caffeine in the evening) with appropriate composition; (iii) regular bedtimes and wake-up times; and (iv) avoidance of long and/or late naps.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40279-021-01601-y.

The Effect of Experimental Recuperative and Appetitive Post-lunch Nap Opportunities, With or Without Caffeine, on Mood and Reaction Time in Highly Trained Athletes

Purpose: To investigate the effects of placebo (PLA), 20 min nap opportunity (N20), 5mg·kg-1 of caffeine (CAF), and their combination (CAF+N20) on sleepiness, mood and reaction-time after partial sleep deprivation (PSD; 04h30 of time in bed; study 1 ) or after normal sleep night (NSN; 08h30 of time in bed; study 2 ). Methods: Twenty-three highly trained athletes ( study 1 ; 9 and study 2 ; 14) performed four test sessions (PLA, CAF, N20 and CAF+N20) in double-blind, counterbalanced and randomized order. Simple (SRT) and two-choice (2CRT) reaction time, subjective sleepiness (ESS) and mood state (POMS) were assessed twice, pre- and post-intervention. Results: SRT was lower (i.e., better performance) during CAF condition after PSD (pre: 336 ± 15 ms vs. post: 312 ± 9 ms; p < 0.001; d = 2.07; Δ% = 7.26) and NSN (pre: 350 ± 39 ms vs. post: 323 ± 32 ms; p < 0.001; d = 0.72; Δ% = 7.71) compared to pre-intervention. N20 decreased 2CRT after PSD (pre: 411 ± 13 ms vs. post: 366 ± 20 ms; p < 0.001; d = 2.89; Δ% = 10.81) and NSN (pre: 418 ± 29 ms vs. post: 375 ± 40 ms; p < 0.001; d = 1.23; Δ% = 10.23). Similarly, 2CRT was shorter during CAF+N20 sessions after PSD (pre: 406 ± 26 ms vs. post: 357 ± 17 ms; p < 0.001; d = 2.17; Δ% = 12.02) and after NSN (pre: 386 ± 33 ms vs. post: 352 ± 30 ms; p < 0.001; d = 1.09; Δ% = 8.68). After PSD, POMS score decreased after CAF (p < 0.001; d = 2.38; Δ% = 66.97) and CAF+N20 (p < 0.001; d = 1.68; Δ% = 46.68). However, after NSN, only N20 reduced POMS (p < 0.001; d = 1.05; Δ% = 78.65) and ESS (p < 0.01; d = 0.71; Δ% = 19.11). Conclusion: After PSD, all interventions reduced sleepiness and only CAF enhanced mood with or without napping. However, only N20 enhanced mood and reduced sleepiness after NSN. Caffeine ingestion enhanced SRT performance regardless of sleep deprivation. N20, with or without caffeine ingestion, enhanced 2CRT independently of sleep deprivation. This suggests a different mode of action of napping and caffeine on sleepiness, mood and reaction time.

Four Weeks of Detraining Induced by COVID-19 Reverse Cardiac Improvements from Eight Weeks of Fitness-Dance Training in Older Adults with Mild Cognitive Impairment

Physical training is considered as a low-cost intervention to generate cardioprotective benefits and to promote physical and mental health, while reducing the severity of acute respiratory infection symptoms in older adults. However, lockdown measures during COVID-19 have limited people's opportunity to exercise regularly. The aim of this study was to investigate the effect of eight weeks of Fitness and Dance training, followed by four weeks of COVID-19-induced detraining, on cardiac adaptations and physical performance indicators in older adults with mild cognitive impairment (MCI). Twelve older adults (6 males and 6 females) with MCI (age, 73 ± 4.4 y; body mass, 75.3 ± 6.4 kg; height, 172 ± 8 cm; MMSE score: 24-27) participated in eight weeks of a combined Fitness-Dance training intervention (two sessions/week) followed by four weeks of training cessation induced by COVID-19 lockdowns. Wireless Polar Team Pro and Polar heart rate sensors (H10) were used to monitor covered distance, speed, heart rate (HR min, avg and max), time in HR zone 1 to 5, strenuousness (load score), beat-to-beat interval (max RR and avg RR) and heart rate variability (HRV-RMSSD). One-way ANOVA was used to analyze the data of the three test sessions (T1: first training session, T2: last training session of the eight-week training program, and T3: first training session after the four-week training cessation). Statistical analysis showed that eight weeks of combined Fitness-Dance training induced beneficial cardiac adaptations by decreasing HR (HR min, HR avg and HR max) with p < 0.001, ES = 0.5-0.6 and Δ = -7 to-9 bpm, and increasing HRV related responses (max and avg RR and RMSSD), with p < 0.01 and ES = 0.4. Consequently, participants spent more time in comfortable HR zones (e.g., p < 0.0005; ES = 0.7; Δ = 25% for HR zone 1) and showed reduced strenuousness (p = 0.02, Δ = -15% for load score), despite the higher covered total distance and average speed (p < 0.01; ES = 0.4). However, these changes were reversed after only four weeks of COVID-19 induced detraining, with values of all parameters returning to their baseline levels. In conclusion, eight weeks of combined Fitness-Dance training seems to be an efficient strategy to promote cardioprotective benefits in older adults with MCI. Importantly, to maintain these health benefits, training has to be continued and detraining periods should be reduced. During a pandemic, home-based exercise programs may provide an effective and efficient alternative of physical training.

A daytime 40-min nap opportunity after a simulated late evening soccer match reduces the perception of fatigue and improves 5-m shuttle run performance

The effect of a 40-min nap opportunity was investigated during the day following a late evening simulated soccer match. Twelve male amateur soccer players (23 ± 3 years; 77.3 ± 5.3 kg; 1.76 ± 0.04 m) performed the Loughborough-intermittent-shuttle test at 21h00 and the following day they completed the sleepiness scale after either a nonap (N0) or 40-min nap (N40) opportunity that began at 14h00. At 17h00, participants performed the 5-m shuttle run test (5mSRT) (6 × 30-s with 35-s in-between; best distance (BD) and total distance (TD) were calculated). After performing the 5mSRT, they provided their rating of the perceived exertion (RPE) and rated their muscle soreness. Sleepiness scores were significantly lower in N40 in comparison with N0 (P < 0.05). A significant increase of TD (+64.5 m) and BD (+9.6 m) after N40 compared to N0 was observed (P < 0.05). The improved performance was associated with reduced levels of muscle soreness and lower RPE. In conclusion, a daytime 40-min nap opportunity after a late evening simulated soccer match improves short-term repetitive maximal performance in soccer players, and has positive effects on perception of sleepiness, muscle soreness, and RPE.

Sleep Quality and Physical Activity as Predictors of Mental Wellbeing Variance in Older Adults during COVID-19 Lockdown: ECLB COVID-19 International Online Survey

BACKGROUND

The COVID-19 lockdown could engender disruption to lifestyle behaviors, thus impairing mental wellbeing in the general population. This study investigated whether sociodemographic variables, changes in physical activity, and sleep quality from pre- to during lockdown were predictors of change in mental wellbeing in quarantined older adults.

METHODS

A 12-week international online survey was launched in 14 languages on 6 April 2020. Forty-one research institutions from Europe, Western-Asia, North-Africa, and the Americas, promoted the survey. The survey was presented in a differential format with questions related to responses "pre" and "during" the lockdown period. Participants responded to the Short Warwick-Edinburgh Mental Wellbeing Scale, the Pittsburgh Sleep Quality Index (PSQI) questionnaire, and the short form of the International Physical Activity Questionnaire.

RESULTS

Replies from older adults (aged >55 years, n = 517), mainly from Europe (50.1%), Western-Asia (6.8%), America (30%), and North-Africa (9.3%) were analyzed. The COVID-19 lockdown led to significantly decreased mental wellbeing, sleep quality, and total physical activity energy expenditure levels (all p < 0.001). Regression analysis showed that the change in total PSQI score and total physical activity energy expenditure (F(2, 514) = 66.41 p < 0.001) were significant predictors of the decrease in mental wellbeing from pre- to during lockdown (p < 0.001, R2: 0.20).

CONCLUSION

COVID-19 lockdown deleteriously affected physical activity and sleep patterns. Furthermore, change in the total PSQI score and total physical activity energy expenditure were significant predictors for the decrease in mental wellbeing.

Distance Motor Learning during the COVID-19 Induced Confinement: Video Feedback with a Pedagogical Activity Improves the Snatch Technique in Young Athletes

The purpose of the present study was to investigate which of two strategies, Video Feedback with Pedagogical Activity (VF-PA) or Video Feedback (VF), would be more beneficial for the remote error correction of the snatch weightlifting technique during the confinement period. Thirty-five school aged children with at least three months of weightlifting experience were randomized to one of three training conditions: VF-PA, VF or the Control group (CONT). Subjects underwent test sessions one week before (T0) and one day after (T1) a six-session training period and a retention test session a week later (T2). During each test session, the Kinovea version 0.8.15 software measured the kinematic parameters of the snatch performance. Following distance learning sessions (T1), the VF-PA improved various kinematic parameters (i.e., barbell horizontal displacements, maximum height, looping and symmetry) compared with T0 (p < 0.5; Cohen's d = 0.58-1.1). Most of these improvements were maintained during the retention test (T2) (p<0.01, Cohen's d = 1.2-1.3) when compared withT0. However, the VF group improved only twoparameters (i.e., barbell symmetry and horizontal displacement) at T1 (p < 0.05; Cohen's d = 0.9), which were not maintained at T2. Better horizontal displacement and looping values were registered during the retention test in the VF-PA group compared with theCONT group (p < 0.05, Cohen's d = 1.49-1.52). The present findings suggest combining video feedback with pedagogical activity during the pandemic induced online coaching or physical education to improve movement learning in school aged children.

Total Sleep Deprivation and Recovery Sleep Affect the Diurnal Variation of Agility Performance: The Gender Differences

ABSTRACT

Romdhani, M, Hammouda, O, Smari, K, Chaabouni, Y, Mahdouani, K, Driss, T, and Souissi, N. Total sleep deprivation and recovery sleep affect the diurnal variation of agility performance: The gender differences. J Strength Cond Res 35(1): 132-140, 2021-This study aimed to investigate the effects of time-of-day, 24 and 36 hours of total sleep deprivation (TSD), and recovery sleep (RS) on repeated-agility performances. Twenty-two physical education students (11 male and 11 female students) completed 5 repeated modified agility T-test (RMAT) sessions (i.e., 2 after normal sleep night [NSN] [at 07:00 and 17:00 hours], 2 after TSD [at 07:00 hours, i.e., 24-hour TSD and at 17:00 hours, i.e., 36-hour TSD], and 1 after RS at 17:00 hours). The RMAT index decreased from the morning to the afternoon after NSN (p < 0.05, d = 1.05; p < 0.01, d = 0.73) and after TSD (p < 0.001, d = 0.92; d = 1.08), respectively, for total time (TT) and peak time (PT). This finding indicates a diurnal variation in repeated agility, which persisted after TSD. However, the diurnal increase in PT was less marked in the female group after NSN (2.98 vs. 6.24%). Moreover, TT and PT increased, respectively, after 24-hour TSD (p < 0.001; d = 0.84, d = 0.87) and 36-hour TSD (p < 0.001, d = 1.12; p < 0.01, d = 0.65). Female subjects' PT was less affected by 24-hour TSD (1.76 vs. 6.81%) compared with male subjects' PT. After 36-hour TSD, the amount of decrease was not different between groups, which increased the diurnal amplitude of PT only for male subjects. Total sleep deprivation suppressed the diurnal increase of PT and increased the diurnal amplitude of oral temperature only in women. Nevertheless, RS normalized the sleep-loss-induced performance disruption. Conclusively, sleep loss and RS differently affect repeated-agility performance of men and women during the day. Sleep extension postdeprivation could have potent restorative effect on repeated-agility performances, and female subjects could extract greater benefits.

The effect of diurnal variation on the performance of exhaustive continuous and alternated-intensity cycling exercises

The purpose of this study was to explore the effect of time of day (TD) on two types of exercise protocols [continuous (CP) versus alternated (AP)]. Eleven physical education students (mean ± SD: age = 24.4 ± 1.2 years, aerobic peak power (APP) = 290 ± 31.9 W) underwent four sessions. These sessions were performed at 08:00 (AM) and 18:00 (PM) and consisted of cycling exercises until voluntary exhaustion at 90% APP (CP) or 70%-105% APP (AP) with the order of testing randomly assigned. Time to exhaustion (time limit = Tlim) was measured from the start of the test to when voluntary exhaustion occurred. Heart rate (HR) was recorded at baseline (HRbaseline) and throughout the protocols to determine HR at exhaustion (HRpeak). Blood lactate ([La]) was measured at rest, immediately after exhaustion and at 2min30 post-exercise to determine [La]peak. A significantly higher means of Tlim (334 ± 57 s; 272 ± 59 s; p< 0.05), HRbaseline (72 ± 5 beats/min; 67 ± 5 beats/min; p< 0.01), HRpeak (186 ± 8 beats/min; 178 ± 9 beats/min; p< 0.01) and [La]peak (16.2 ± 2.1 mmol/l; 13.9 ± 1.9 mmol/l; p< 0.05) were observed in CP at the PM compared to the AM. In addition, a significant higher means of Tlim (380 ± 54 s; 312 ± 82 s; p< 0.05), HRbaseline (73.1 ± 5.5 beats/min; 67 ± 5.4 beats/min; p< 0.01), HRpeak (186 ± 8 beats/min; 180 ± 9 beats/min; p< 0.05) and [La]peak (17.9 ± 1.8 mmol/l; 14.7 ± 2.1 mmol/l; p< 0.01) were observed in AP at the PM compared to the AM. It is concluded that AP and CP are more appropriate in the late afternoon than in the morning for performing long-lasting exercises. The AP could be a novel strategy for increasing the engagement in physical activity.

Psychological consequences of COVID-19 home confinement: The ECLB-COVID19 multicenter study

BACKGROUND

Public health recommendations and government measures during the COVID-19 pandemic have enforced restrictions on daily-living. While these measures are imperative to abate the spreading of COVID-19, the impact of these restrictions on mental health and emotional wellbeing is undefined. Therefore, an international online survey (ECLB-COVID19) was launched on April 6, 2020 in seven languages to elucidate the impact of COVID-19 restrictions on mental health and emotional wellbeing.

METHODS

The ECLB-COVID19 electronic survey was designed by a steering group of multidisciplinary scientists, following a structured review of the literature. The survey was uploaded and shared on the Google online-survey-platform and was promoted by thirty-five research organizations from Europe, North-Africa, Western-Asia and the Americas. All participants were asked for their mental wellbeing (SWEMWS) and depressive symptoms (SMFQ) with regard to "during" and "before" home confinement.

RESULTS

Analysis was conducted on the first 1047 replies (54% women) from Asia (36%), Africa (40%), Europe (21%) and other (3%). The COVID-19 home confinement had a negative effect on both mental-wellbeing and on mood and feelings. Specifically, a significant decrease (p < .001 and Δ% = 9.4%) in total score of the SWEMWS questionnaire was noted. More individuals (+12.89%) reported a low mental wellbeing "during" compared to "before" home confinement. Furthermore, results from the mood and feelings questionnaire showed a significant increase by 44.9% (p < .001) in SMFQ total score with more people (+10%) showing depressive symptoms "during" compared to "before" home confinement.

CONCLUSION

The ECLB-COVID19 survey revealed an increased psychosocial strain triggered by the home confinement. To mitigate this high risk of mental disorders and to foster an Active and Healthy Confinement Lifestyle (AHCL), a crisis-oriented interdisciplinary intervention is urgently needed.

Effect of Ramadan intermittent fasting on cognitive, physical and biochemical responses to strenuous short-term exercises in elite young female handball players

The present study aimed to assess the effect of Ramadan intermittent fasting (RF) on cognitive and physical performance and biochemical responses to specific exercises in elite young female handball players. Twelve athletes participated in three experimental sessions: one week before Ramadan (BR), during the first week of Ramadan (FWR) and during the last week of Ramadan (LWR). The present crossover study was carried out in Tunisia during the 2013 Ramadan month lasting from 9 July to 7 august. During each session, a battery of tests was performed as follow: Hooper index, vigilance test (VT), Epworth sleepiness scale (ESS), five jump test (5-JT), modified agility T-test (MAT), maximal standing ball-throw velocity test (MSBVT) and Running-based Anaerobic Sprint (RAST) Test. Rating of perceived exertion (RPE) was recorded immediately after the RAST. Blood samples were collected before and after exercises during each session. The results showed that ESS scores were higher during LWR than BR (p < 0.05). Moreover, MSBVT time decreased (p < 0.05) during LWR, therefore performance enhanced. The power of three final sprints from the RAST decreased significantly only during LWR compared to BR (p < 0.05). RAST fatigue index and RPE scores were higher during LWR more than BR (p < 0.05). The results showed also that hematological measures (i.e., red blood cells, hemoglobin and hematocrit), plasma osmolarity and energetic markers were unaffected by RF. Biomarkers of muscle damage were higher after the RAST only during LWR compared to BR (p < 0.01 for all). In conclusion, RF increased ESS and decreased RAST performances associated with higher muscle damage and fatigue, especially at LWR. These previous alterations could be attributed to disturbances of sleep and circadian rhythms rather than nutritional deficiency or dehydratation.

Moderators of the Impact of (Poly)Phenols Interventions on Psychomotor Functions and BDNF: Insights from Subgroup Analysis and Meta-Regression

BACKGROUND

Recent anti-aging interventions have shown contradictory impacts of (poly)phenols regarding the prevention of cognitive decline and maintenance of brain function. These discrepancies have been linked to between-study differences in supplementation protocols. This subgroup analysis and meta-regression aimed to (i) examine differential effects of moderator variables related to participant characteristics and supplementation protocols and (ii) identify practical recommendations to design effective (poly)phenol supplementation protocols for future anti-aging interventions.

METHODS

Multiple electronic databases (Web of Science; PubMed) searched for relevant intervention published from inception to July 2019. Using the PICOS criteria, a total of 4303 records were screened. Only high-quality studies (n = 15) were included in the final analyses. Random-effects meta-analysis was used, and we calculated standard differences in means (SDM), effect size (ES), and 95% confidence intervals (CI) for two sufficiently comparable items (i.e., psychomotor function and brain-derived neurotrophic factor (BDNF)). When significant heterogeneity was computed (I² > 50%), a subgroup and meta-regression analysis were performed to examine the moderation effects of participant characteristics and supplementation protocols.

RESULTS

The reviewed studies support the beneficial effect of (poly)phenols-rich supplementation on psychomotor functions (ES = -0.677, p = 0.001) and brain plasticity (ES = 1.168, p = 0.028). Subgroup analysis revealed higher beneficial impacts of (poly)phenols (i) in younger populations compared to older (SDM = -0.89 vs. -0.47 for psychomotor performance, and 2.41 vs. 0.07 for BDNF, respectively), (ii) following an acute compared to chronic supplementation (SDM = -1.02 vs. -0.43 for psychomotor performance), and (iii) using a phenolic compound with medium compared to low bioavailability rates (SDM = -0.76 vs. -0.68 for psychomotor performance and 3.57 vs. 0.07 for DBNF, respectively). Meta-regressions revealed greater improvement in BDNF levels with lower percentages of female participants (Q = 40.15, df = 6, p < 0.001) and a skewed scatter plot toward a greater impact using higher (poly)phenols doses.

CONCLUSION

This review suggests that age group, gender, the used phenolic compounds, their human bioavailability rate, and the supplementation dose as the primary moderator variables relating to the beneficial effects of (poly)phenol consumption on cognitive and brain function in humans. Therefore, it seems more advantageous to start anti-aging (poly)phenol interventions in adults earlier in life using medium (≈500 mg) to high doses (≈1000 mg) of phenolic compounds, with at least medium bioavailability rate (≥9%).

Partial sleep deprivation affects endurance performance and psychophysiological responses during 12-minute self-paced running exercise

PURPOSE

This study aimed to investigate the effects of partial sleep deprivation (PSD) on physical performance and psychophysiological responses during 12-minute self-paced running exercise.

METHODS

Twenty runners (20.8±1.1 years, 70.6±4.9 kg, 175.1±3.9 cm) performed, in a randomized order, two running self-paced field exercises after a normal sleep night (CONT, bedtime from 22:30 h to 06:30 h) and one night of PSD (bedtime from 00:30 h to 04:30 h). Core temperature and motivation were recorded before exercise. Speed, covered distance, heart rate (HR), rating of perceived exertion (RPE) and respiratory parameters (i.e., minute ventilation (VE), oxygen uptake (VO₂) and carbon dioxide production (VCO₂)) were assessed during exercise. Blood lactate concentration [La] was assessed 2 min after exercise. Simple reaction time (SRT), mood and barrage test (BT) were assessed before and after exercise.

RESULTS

Higher RPE (p=0.01, d=0.90) and lower physical performance (i.e., p=0.001, d=0.59 for running speed and p=0.01, d=0.7 and Δ (%)=-6% for covered distance), following PSD, were obtained compared to CONT. Similarly, PSD attenuated core temperature (p=0.01, d=0.84), HR (p=0.006, ɳp²=0.45), VE (p=0.001, ɳp²=0.73), VO₂ (p=0.001, ɳp²=0.96), BT (p<0.0005, ɳp²=0.86), SRT (p=0.0009, ɳp²=0.44) and mood (p<0.0005). However, VCO₂, [La] and motivation score were not affected by sleep conditions.

CONCLUSION

The decrease of running performance and the increase of physical discomfort after PSD could be the origin of the lower cardio-respiratory responses to the 12-minute self-paced exercise. Effective strategies should be introduced to overcome the deterioration of physical performance and physiological responses after PSD.

COVID-19 Home Confinement Negatively Impacts Social Participation and Life Satisfaction: A Worldwide Multicenter Study

Public health recommendations and governmental measures during the new coronavirus disease (COVID-19) pandemic have enforced numerous restrictions on daily living including social distancing, isolation, and home confinement. While these measures are imperative to mitigate spreading of COVID-19, the impact of these restrictions on psychosocial health is undefined. Therefore, an international online survey was launched in April 2020 to elucidate the behavioral and lifestyle consequences of COVID-19 restrictions. This report presents the preliminary results from more than one thousand responders on social participation and life satisfaction.

METHODS

Thirty-five research organizations from Europe, North-Africa, Western Asia, and the Americas promoted the survey through their networks to the general society, in 7 languages (English, German, French, Arabic, Spanish, Portuguese, and Slovenian). Questions were presented in a differential format with questions related to responses "before" and "during" confinement conditions.

RESULTS

1047 participations (54% women) from Asia (36%), Africa (40%), Europe (21%), and others (3%) were included in the analysis. Findings revealed psychosocial strain during the enforced COVID-19 home confinement. Large decreases (p < 0.001) in the amount of social activity through family (-58%), friends/neighbors (-44.9%), or entertainment (-46.7%) were triggered by the enforced confinement. These negative effects on social participation were also associated with lower life satisfaction (-30.5%) during the confinement period. Conversely, the social contact score through digital technologies significantly increased (p < 0.001) during the confinement period with more individuals (+24.8%) being socially connected through digital technology.

CONCLUSION

These preliminary findings elucidate the risk of psychosocial strain during the early COVID-19 home confinement period in 2020. Therefore, in order to mitigate the negative psychosocial effects of home confinement, implementation of national strategies focused on promoting social inclusion through a technology-based solution is strongly suggested.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Effects of Mental Effort on Premotor Muscle Activity and Maximal Grip Force

The present study sought to evaluate how mental effort modulates premotor activity within forearm muscles in the context of an isometric grasping task. Muscle activity of the flexor digitorum superficialis (FDS) and extensor digitorum communis (EDC) was recorded during the application of maximum grip forces in nineteen healthy adult subjects. Each subject was examined under two experimental conditions: 1) spontaneous initiation of grasp (SI) and 2) focused concentration preceding the initiation of grasp (CA). Two novel parameters, the mean premotor duration (MPD) and the mean premotor power (MPP) were used to distinguish patterns of muscle activity. Here we tested the hypothesis was maximal grip strength is primed by muscle activity during the premotor phase. Our results demonstrate that MPD for each muscle group was significantly longer in the CA condition than for the SI condition (BF₁₀ = 491497) and that MPP was significantly greater in EDC than in FDS (BF₁₀ = 4305). Furthermore, both the MPD and MPP of the EDC were significantly correlated with maximum grip force. These results suggest that the increase of premotor activity consequent to the mental effort (focused concentration) may support internal biomechanical and physiological mechanisms which serve to enhance patterns of neuromuscular synergies.

Effects of COVID-19 Home Confinement on Eating Behaviour and Physical Activity: Results of the ECLB-COVID19 International Online Survey

BACKGROUND

Public health recommendations and governmental measures during the COVID-19 pandemic have resulted in numerous restrictions on daily living including social distancing, isolation and home confinement. While these measures are imperative to abate the spreading of COVID-19, the impact of these restrictions on health behaviours and lifestyles at home is undefined. Therefore, an international online survey was launched in April 2020, in seven languages, to elucidate the behavioural and lifestyle consequences of COVID-19 restrictions. This report presents the results from the first thousand responders on physical activity (PA) and nutrition behaviours.

METHODS

Following a structured review of the literature, the "Effects of home Confinement on multiple Lifestyle Behaviours during the COVID-19 outbreak (ECLB-COVID19)" Electronic survey was designed by a steering group of multidisciplinary scientists and academics. The survey was uploaded and shared on the Google online survey platform. Thirty-five research organisations from Europe, North-Africa, Western Asia and the Americas promoted the survey in English, German, French, Arabic, Spanish, Portuguese and Slovenian languages. Questions were presented in a differential format, with questions related to responses "before" and "during" confinement conditions.

RESULTS

1047 replies (54% women) from Asia (36%), Africa (40%), Europe (21%) and other (3%) were included in the analysis. The COVID-19 home confinement had a negative effect on all PA intensity levels (vigorous, moderate, walking and overall). Additionally, daily sitting time increased from 5 to 8 h per day. Food consumption and meal patterns (the type of food, eating out of control, snacks between meals, number of main meals) were more unhealthy during confinement, with only alcohol binge drinking decreasing significantly.

CONCLUSION

While isolation is a necessary measure to protect public health, results indicate that it alters physical activity and eating behaviours in a health compromising direction. A more detailed analysis of survey data will allow for a segregation of these responses in different age groups, countries and other subgroups, which will help develop interventions to mitigate the negative lifestyle behaviours that have manifested during the COVID-19 confinement.

Effects of COVID-19 Home Confinement on Eating Behaviour and Physical Activity: Results of the ECLB-COVID19 International Online Survey

BACKGROUND

Public health recommendations and governmental measures during the COVID-19 pandemic have resulted in numerous restrictions on daily living including social distancing, isolation and home confinement. While these measures are imperative to abate the spreading of COVID-19, the impact of these restrictions on health behaviours and lifestyles at home is undefined. Therefore, an international online survey was launched in April 2020, in seven languages, to elucidate the behavioural and lifestyle consequences of COVID-19 restrictions. This report presents the results from the first thousand responders on physical activity (PA) and nutrition behaviours.

METHODS

Following a structured review of the literature, the "Effects of home Confinement on multiple Lifestyle Behaviours during the COVID-19 outbreak (ECLB-COVID19)" Electronic survey was designed by a steering group of multidisciplinary scientists and academics. The survey was uploaded and shared on the Google online survey platform. Thirty-five research organisations from Europe, North-Africa, Western Asia and the Americas promoted the survey in English, German, French, Arabic, Spanish, Portuguese and Slovenian languages. Questions were presented in a differential format, with questions related to responses "before" and "during" confinement conditions.

RESULTS

1047 replies (54% women) from Asia (36%), Africa (40%), Europe (21%) and other (3%) were included in the analysis. The COVID-19 home confinement had a negative effect on all PA intensity levels (vigorous, moderate, walking and overall). Additionally, daily sitting time increased from 5 to 8 h per day. Food consumption and meal patterns (the type of food, eating out of control, snacks between meals, number of main meals) were more unhealthy during confinement, with only alcohol binge drinking decreasing significantly.

CONCLUSION

While isolation is a necessary measure to protect public health, results indicate that it alters physical activity and eating behaviours in a health compromising direction. A more detailed analysis of survey data will allow for a segregation of these responses in different age groups, countries and other subgroups, which will help develop interventions to mitigate the negative lifestyle behaviours that have manifested during the COVID-19 confinement.

Effects of COVID-19 Home Confinement on Eating Behaviour and Physical Activity: Results of the ECLB-COVID19 International Online Survey

BACKGROUND

Public health recommendations and governmental measures during the COVID-19 pandemic have resulted in numerous restrictions on daily living including social distancing, isolation and home confinement. While these measures are imperative to abate the spreading of COVID-19, the impact of these restrictions on health behaviours and lifestyles at home is undefined. Therefore, an international online survey was launched in April 2020, in seven languages, to elucidate the behavioural and lifestyle consequences of COVID-19 restrictions. This report presents the results from the first thousand responders on physical activity (PA) and nutrition behaviours.

METHODS

Following a structured review of the literature, the "Effects of home Confinement on multiple Lifestyle Behaviours during the COVID-19 outbreak (ECLB-COVID19)" Electronic survey was designed by a steering group of multidisciplinary scientists and academics. The survey was uploaded and shared on the Google online survey platform. Thirty-five research organisations from Europe, North-Africa, Western Asia and the Americas promoted the survey in English, German, French, Arabic, Spanish, Portuguese and Slovenian languages. Questions were presented in a differential format, with questions related to responses "before" and "during" confinement conditions.

RESULTS

1047 replies (54% women) from Asia (36%), Africa (40%), Europe (21%) and other (3%) were included in the analysis. The COVID-19 home confinement had a negative effect on all PA intensity levels (vigorous, moderate, walking and overall). Additionally, daily sitting time increased from 5 to 8 h per day. Food consumption and meal patterns (the type of food, eating out of control, snacks between meals, number of main meals) were more unhealthy during confinement, with only alcohol binge drinking decreasing significantly.

CONCLUSION

While isolation is a necessary measure to protect public health, results indicate that it alters physical activity and eating behaviours in a health compromising direction. A more detailed analysis of survey data will allow for a segregation of these responses in different age groups, countries and other subgroups, which will help develop interventions to mitigate the negative lifestyle behaviours that have manifested during the COVID-19 confinement.

Effects of Aerobic-, Anaerobic- and Combined-Based Exercises on Plasma Oxidative Stress Biomarkers in Healthy Untrained Young Adults

Currently, it is well accepted that physical exercise-induced oxidative stress may damage biological structures and impair cellular functions. However, it is still unclear which type of exercise results in the greatest oxidative stress responses among a healthy untrained population. The aim of the present study was to compare the acute oxidative stress response (i.e., 0 to 20 min) following different types of exercise (anaerobic, aerobic, and combined). Ten healthy, untrained males (19.5 ± 1.7 years) performed three randomized exercise bouts: anaerobic (30 s Wingate test), aerobic (30 min at 60% maximal aerobic power (MAP)) or combined (anaerobic and aerobic). Venous blood samples were collected before, as well as at 0 (P0), 5 (P5), 10 (P10), and 20 (P20) min after each session. Rates of malondialdehyde (MDA) and antioxidant activities (i.e., glutathione peroxidase (GPX), superoxide dismutase (SOD), glutathione reductase (GR), α-tocopherol, and total antioxidant status (TAS)) were assessed. Independent of exercise type, plasma MDA, GPX, SOD, and GR contents increased above baseline, whereas plasma α-tocopherol decreased under baseline after the test sessions (p < 0.05). Aerobic and anaerobic exercises generated faster responses (at P0) when compared to the combined exercise (P5 to P10) for the majority of the tested parameters. Plasma TAS content only increased following the aerobic exercise at P10 (p = 0.03). Five to twenty-minutes post exercise, the highest MDA response was registered in the aerobic condition, and the highest GPX and SOD responses were recorded in the anaerobic (at P5) and aerobic (at P20) conditions (p < 0.05). In conclusion, aerobic, anaerobic, or combined exercises have the potential to acutely increase oxidative stress and antioxidant activities, but with different responses magnitude. These findings confirm that oxidative stress response seems to be dependent on the intensity and the duration of the physical exercise and may help in understanding how varying exercise bouts influence the degree of oxidative stress among healthy untrained young adults.

The Effect of (Poly)phenol-Rich Interventions on Cognitive Functions and Neuroprotective Measures in Healthy Aging Adults: A Systematic Review and Meta-Analysis

Context: As the food industry is continually involved in the development of new attractive alternative therapeutic agents, the evaluation of the beneficial impact of (poly)phenols on cognitive and brain function during aging has gained increasing interest. Objective: This systematic review and meta-analysis aimed to evaluate the acute and chronic effects of (poly)phenol-rich diet supplementation on cognitive function and brain health in aging adults. Data Sources: PubMed and Web of Science databases were searched for relevant randomized placebo-controlled trials (RCTs) published from inception to July 2019. Study Selection: Two researchers independently screened 4303 records, using the PICOS criteria: Participants were aging adults; Intervention was based on acute and/or chronic (poly)phenols-rich supplementation; Comparator was any comparator; Outcomes included cognitive function and neuroprotective measures; and Study design was RCTs. A third researcher was consulted when discrepancies arose. Fifteen high-quality (mean PEDro score = 8.8 ± 0.56) RCTs (total participants: 918 healthy older adults) were included in the final sample. Data Extraction: Information on study design, employed treatment, characteristics of participants, outcomes, and the correspondent assessing methods were extracted. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. Data Analysis and Results: A random-effects meta-analysis was used to pool estimates across studies. Effect size (ES) and its 95% confidence interval (CI) was calculated. Pooled results yielded a trivial ES (−0.2 to 0.03) for brain-derived neurotrophic factor and neuroinflammatory parameters and small (0.36) to moderate (0.82) ES for executive functions. Conclusion: This meta-analysis failed to provide evidence regarding the neuroprotective and anti-inflammatory effect of (poly)phenols supplementation in aging adults. However, findings from individual studies, included in this systematic review, suggest polyphenol-rich supplementation may improve some cognitive and brain functions in older adults. The beneficial effect of polyphenols seems to depend on ingested dose and bioavailability. Results suggest at least an intermediate dose (≥500 mg), and intermediate (≈9%) to high (43%) bioavailability rates are needed to cross the brain blood barrier and to exert a significant effect on cognitive health.

Effects of natural polyphenol-rich pomegranate juice on the acute and delayed response of Homocysteine and steroidal hormones following weightlifting exercises: a double-blind, placebo-controlled trial

BACKGROUND

Maximal strength-speed exercise is a powerful stimulus to acutely increase concentrations of circulating steroid hormones and homocysteine [Hcy]. There is some evidence that antioxidant beverages rich in polyphenols can attenuate [Hcy] levels and modulate endocrine responses in favor of an anabolic environment. Polyphenols-rich pomegranate (POM) have been reported to possess one of the highest antioxidant capacities compared to other purported nutraceuticals and other food stuffs. Studies focused on proving the beneficial effect of POM consumption during maximal strength exercises have only measured physical performance, muscle damage, oxidative stress and inflammatory responses, while POM effects on [Hcy] and hormonal adaptations are lacking. The aim of the present study was to investigate the effect of consuming natural polyphenol-rich pomegranate juice (POMj) on the acute and delayed [Hcy] and steroidal hormonal responses to a weightlifting exercises session.

METHODS

Nine elite weightlifters (21.0 ± 1 years) performed two Olympic-weightlifting sessions after ingesting either the placebo (PLA) or POMj supplements. Venous blood samples were collected at rest and 3 min and 48 h after each session.

RESULTS

Compared to baseline values, circulating cortisol [C] decreased (p < 0.01) and testosterone/cortisol [T/C] ratio increased immediately following the training session in both PLA and POMj conditions (p = 0.003 for PLA and p = 0.02 for POM). During the 48 h recovery period, all tested parameters were shown to recover to baseline values in both conditions with significant increases in [C] and decreases in [T/C] (p < 0.01 for PLA and p < 0.05 for POMj) from 3 min to 48 h post-exercises. Compared to PLA, a lower level of plasma testosterone [T] was registered 3 min post exercise using POMj supplementation (p = 0.012) and a significant decrease (p = 0.04, %change = - 14%) in plasma [Hcy] was registered during the 48 h recovery period only using POMj. A moderate correlation was observed between [Hcy] and [T] responses (p = 0.002, r = - 0.50).

CONCLUSION

In conclusion, supplementation with POMj has the potential to attenuate the acute plasma [T] response, but did not effect 48 h recovery kinetics of [Hcy] following weightlifting exercise. Further studies investigating androgen levels in both plasma and muscular tissue are needed to resolve the functional consequences of the observed acute POMj effect on plasma [T].

TRIAL REGISTRATION

Clinical Trials.gov, ID: NCT02697903. Registered 03 March 2016.

Psychological consequences of COVID-19 home confinement: The ECLB-COVID19 multicenter study

BACKGROUND

Public health recommendations and government measures during the COVID-19 pandemic have enforced restrictions on daily-living. While these measures are imperative to abate the spreading of COVID-19, the impact of these restrictions on mental health and emotional wellbeing is undefined. Therefore, an international online survey (ECLB-COVID19) was launched on April 6, 2020 in seven languages to elucidate the impact of COVID-19 restrictions on mental health and emotional wellbeing.

METHODS

The ECLB-COVID19 electronic survey was designed by a steering group of multidisciplinary scientists, following a structured review of the literature. The survey was uploaded and shared on the Google online-survey-platform and was promoted by thirty-five research organizations from Europe, North-Africa, Western-Asia and the Americas. All participants were asked for their mental wellbeing (SWEMWS) and depressive symptoms (SMFQ) with regard to "during" and "before" home confinement.

RESULTS

Analysis was conducted on the first 1047 replies (54% women) from Asia (36%), Africa (40%), Europe (21%) and other (3%). The COVID-19 home confinement had a negative effect on both mental-wellbeing and on mood and feelings. Specifically, a significant decrease (p < .001 and Δ% = 9.4%) in total score of the SWEMWS questionnaire was noted. More individuals (+12.89%) reported a low mental wellbeing "during" compared to "before" home confinement. Furthermore, results from the mood and feelings questionnaire showed a significant increase by 44.9% (p < .001) in SMFQ total score with more people (+10%) showing depressive symptoms "during" compared to "before" home confinement.

CONCLUSION

The ECLB-COVID19 survey revealed an increased psychosocial strain triggered by the home confinement. To mitigate this high risk of mental disorders and to foster an Active and Healthy Confinement Lifestyle (AHCL), a crisis-oriented interdisciplinary intervention is urgently needed.

Psychological consequences of COVID-19 home confinement: The ECLB-COVID19 multicenter study

BACKGROUND

Public health recommendations and government measures during the COVID-19 pandemic have enforced restrictions on daily-living. While these measures are imperative to abate the spreading of COVID-19, the impact of these restrictions on mental health and emotional wellbeing is undefined. Therefore, an international online survey (ECLB-COVID19) was launched on April 6, 2020 in seven languages to elucidate the impact of COVID-19 restrictions on mental health and emotional wellbeing.

METHODS

The ECLB-COVID19 electronic survey was designed by a steering group of multidisciplinary scientists, following a structured review of the literature. The survey was uploaded and shared on the Google online-survey-platform and was promoted by thirty-five research organizations from Europe, North-Africa, Western-Asia and the Americas. All participants were asked for their mental wellbeing (SWEMWS) and depressive symptoms (SMFQ) with regard to "during" and "before" home confinement.

RESULTS

Analysis was conducted on the first 1047 replies (54% women) from Asia (36%), Africa (40%), Europe (21%) and other (3%). The COVID-19 home confinement had a negative effect on both mental-wellbeing and on mood and feelings. Specifically, a significant decrease (p < .001 and Δ% = 9.4%) in total score of the SWEMWS questionnaire was noted. More individuals (+12.89%) reported a low mental wellbeing "during" compared to "before" home confinement. Furthermore, results from the mood and feelings questionnaire showed a significant increase by 44.9% (p < .001) in SMFQ total score with more people (+10%) showing depressive symptoms "during" compared to "before" home confinement.

CONCLUSION

The ECLB-COVID19 survey revealed an increased psychosocial strain triggered by the home confinement. To mitigate this high risk of mental disorders and to foster an Active and Healthy Confinement Lifestyle (AHCL), a crisis-oriented interdisciplinary intervention is urgently needed.

Effects of Playing Surface on Physical, Physiological, and Perceptual Responses to a Repeated-Sprint Ability Test: Natural Grass Versus Artificial Turf

PURPOSE

The effect of playing surface on physical performance during a repeated-sprint ability (RSA) test and the mechanisms for any potential playing-surface-dependent effects on RSA performance are equivocal. The purpose of this study was to investigate the effect of natural grass (NG) and artificial turf (AT) on physical performance, ratings of perceived exertion, feeling scale, and blood biomarkers related to anaerobic contribution (blood lactate [Lac]), muscle damage (creatine kinase and lactate dehydrogenase), inflammation (C-reactive protein), and immune function (neutrophils [NEU], lymphocytes [LYM], and monocytes) in response to an RSA test.

METHODS

A total of 9 male professional football players from the same regional team completed 2 sessions of RSA testing (6 × 30 s interspersed with a 35-s recovery) on NG and AT in a randomized order. During the RSA test, total (sum of distances) and peak (highest distance covered in a single repetition) distance covered were determined using a measuring tape, and the decrement in sprinting performance from the first to the last repetition was calculated. Before and after the RSA test, ratings of perceived exertion, feeling scale, and Lac, creatine kinase, lactate dehydrogenase, C-reactive protein, NEU, LYM, and monocytes were recorded in both NG and AT conditions.

RESULTS

Although physical performance declined during the RSA blocks on both surfaces (P = .001), the distance covered declined more on NG (15%) than on AT (11%; P = .04; effect size [ES] = -0.34; 95% confidence interval [CI], -1.21 to 0.56) with a higher total distance covered (+6% [2%]) on AT (P = .018; ES = 1.15; 95% CI, 0.16 to 2.04). In addition, lower ratings of perceived exertion (P = .04; ES = -0.49; 95% CI, -1.36 to 0.42), Lac, NEU, and LYM (P = .03; ES = -0.80; 95% CI, -1.67 to 0.14; ES = -0.16; 95% CI, -1.03 to 0.72; and ES = -0.94; 95% CI, -1.82 to 0.02, respectively) and more positive feelings (P = .02; ES = 0.81; 95% CI, -0.13 to 1.69) were observed after the RSA test performed on AT than on NG. No differences were observed in the remaining physical and blood markers.

CONCLUSION

These findings suggest that RSA performance is enhanced on AT compared with NG. This effect was accompanied by lower fatigue perception and Lac, NEU, and LYM and a more pleasurable feeling. These observations might have implications for physical performance in intermittent team-sport athletes who train and compete on different playing surfaces.

Comparison of 2- and 3-Minute Inter-Repetition Rest Periods on Maximal Jerk Technique and Power Maintenance

Purpose: The aim of this study was to examine the effect of 3- vs. 2-minute inter maximal-repetition rest period (IMRRP) on maintaining jerk technical efficiency and power production during two successive maximal repetitions of Clean & Jerk (C&J). Methods: In a randomized, within subject, repeated measures design, nine elite-weightlifters (age: 24.4 ± 3.6 years, body mass: 77.2 ± 7.1 kg, height 176.0 ± 6.4 cm and 1RM C&J: 170.0 ± 5.0 kg) performed 2-separate testing sessions using 2 (IMRRP-2) and 3 (IMRRP-3) -minute IMRRP, while barbell kinematics and kinetics and joint kinematics were recorded. Results: Statistical analysis showed that one minute longer IMRRP enhanced the maintenance of optimal jerk technique evidenced by reducing declines in peak vertical barbell displacement (2.74%; p = .03), peak barbell velocity (2.89%; p = .03), and peak knee (1.61%; p = .03) and hip extensions (1.59%; p = .03) during the drive phase of the jerk. Additionally, IMRRP-3 led to maintaining optimal lifting strategy by reducing the increase in horizontal displacement during the descending (3.85%; p = .04) and ascending (5.42%; p = .02) phases. Increasing IMRRP from 2min to 3min was also shown to enhance kinetic variables evidenced by prompting higher peak vGRF (2.01%; p = .04) and power (2.55%; p = .04). Conclusion: To better identify an athlete's maximal jerk technique and power maintenance, the results of this study suggest 3min as more appropriate IMRRP during successive C&J at 100% 1RM.

Sleep deprivation affects post-lunch dip performances, biomarkers of muscle damage and antioxidant status

To compare the effects of two types of partial sleep deprivation (PSD) at the beginning (PSDBN) and the end (PSDEN) of the night on mood, cognitive performances, biomarkers of muscle damage, haematological status and antioxidant responses before and after repeated-sprint exercise in the post-lunch dip. Fourteen male athletes performed the Running-based Anaerobic Sprint Test following: (i) baseline normal sleep night, (ii) PSDBN, or (iii) PSDEN in a randomized and counter-balanced order. During each condition, participants performed simple and choice reaction time tests, the Profile of Mood States, subjective sleepiness, and the Running-based Anaerobic Sprint Test. Plasma biomarkers of muscle damage, total blood count, and antioxidant activities were measured at rest and after the repeated sprint in the three conditions. PSDEN decreased Pmax (p=0.008; d=1.12), Pmean (p=0.002; d=1.33) and Pmin (p=0.006; d=1.15), whilst PSDBN decreased Pmean (p=0.04; d=0.68) and Pmin (p=0.028; d=0.58), in comparison with baseline. PSDEN exerted stronger effects on Pmax (p=0.013; d=0.74) and Pmean (p=0.048; d=0.54) than PSDBN. Moreover, PSDEN increased subjective sleepiness (p<0.001; d=1.93), while PSDBN impaired choice reaction time (p<0.001, d=1.89). Both PSD types decreased resting glutathione peroxidase (p<0.001; d=5.43, d=3.86), and increased aspartate amino-transferase levels (p<0.001; d=1.36, d=1.37) respectively for PSDEN and PSDBN. PSDEN decreased repeated-sprint performances more than PSDBN in the post-lunch dip. This could be explained by the lowered mood and resting antioxidant status and the increased inflammatory profile after PSDEN. Repeated-sprint exercise resulted in greater inflammation after PSDEN, despite the decreased physical performance. The drop of resting antioxidant defence and haemoglobin concentration after PSDEN could explain the increased sleep drive at the post-lunch dip.

Effect of melatonin ingestion on physical performance, metabolic responses, and recovery after an intermittent training session

Objectives

Fatigue is a limiting factor for sport performance. For this reason, optimal recovery after training is just as critical as the training program itself, if not more. Indeed, there is a need for strategies that can facilitate recovery after training, and one such strategy is the ingestion of supplements like melatonin (MEL). This study aimed to evaluate if MEL intake could improve recovery of athletes after an intermittent training session (ITS).

Methods

Fifteen elite female athletes (17.4 ± 0.4 years, 76.4 ± 5.6 kg, 1.76 ± 0.04 m; mean ± standard deviation) participated in two testing campaigns. During each period, they performed a battery of physical and cognitive tests before and after an ITS, as well as after ingesting MEL (6 mg tablet) or placebo in a randomized design. The ITS comprised the modified agility T-test, squat jump, counter movement jump, maximum standing ball-throw velocity test, maximum jump ball-throw velocity test, and 20-m sprint. Oral temperature (OT) and vigilance were evaluated before and after the ITS. Rating of perceived exertion (RPE), blood lactate [La], and glucose [Gl] were recorded after each ITS.

Results

Short-term performance, recovery of physical performance, and OT were not affected by MEL ingestion after the ITS. Moreover, MEL did not affect cognitive performance or RPE scores after the ITS. However, [La] and [Gl] (p < 0.05 for both) were decreased after MEL ingestion.

Conclusion

MEL has no effect on the recovery of physical performance but may affect glucose utilization and lactate metabolism during the team-handball training session.

Effect of 2- vs. 3-Minute Interrepetition Rest Period on Maximal Clean Technique and Performance

Ammar, A, Riemann, BL, Abdelkarim, O, Driss, T, and Hökelmann, A. Effect of 2- vs. 3-minute interrepetition rest period on maximal clean technique and performance. J Strength Cond Res 34(9): 2548-2556, 2020-Currently, it is widely accepted that adopting a long rest period (3-5 minutes) during maximal strength and power exercise is of importance in reducing acute fatigue and maintaining power and technique proficiency. However, despite the fact that weightlifting is an example of maximal strength exercise, only 2 minutes are officially allowed when athletes attempt 2 successive lifts. The purpose of this study was to compare 3- vs. 2-minute intermaximal repetition rest periods (IMRRPs) on performance, rate of perceived exertion (RPE), technical efficiency, and power production during 2 successive maximal repetitions of clean & jerk (C&J). Nine elite weightlifters (age: 24.4 ± 3.6 years, body mass: 77.2 ± 7.1 kg, height 176.0 ± 6.4 cm, and 1 repetition maximum C&J: 170.0 ± 5.0 kg) performed 2 separate testing sessions using 2-minute IMRRP (IMRRP-2) and 3-minute IMRRP (IMRRP-3), in a randomized order, while barbell kinematics and kinetics were recorded. Results showed that the longer IMRRP-3 minutes led to the maintenance of clean technique (from the first to the second repetition) evidenced by a 1.86% lower decline in peak vertical displacement (p = 0.03) and attenuation of increased peak horizontal displacements with a 1.74% (p = 0.03) less backward movement during the first pull, a 3.89% (p = 0.008) less forward movement during the second pull, and a 4.7% (p = 0.005) less backward movement during the catch phase. In addition, attenuation of peak velocity (2.22%; p = 0.02), peak vertical ground reaction force (1.70%; p = 0.03), and peak power (2.14%; p = 0.02) declines were shown using IMRRP-3 compared with IMRRP-2. Increasing IMRRP from 2 to 3 minutes was also shown to decrease RPE values (8.02%; p = 0.008) and to enhance supramaximal C&J performance (1.55%; p = 0.003). The results of this study suggest 3 minutes to be the most advantageous IMRRP in terms of maintaining technical efficiency, power output, reducing fatigue perception, and enhancing performance in elite weightlifters.

Melatonin ingestion after exhaustive late-evening exercise improves sleep quality and quantity, and short-term performances in teenage athletes

The present study aimed to explore the effects of a single 10-mg dose of melatonin (MEL) administration after exhaustive late-evening exercise on sleep quality and quantity, and short-term physical and cognitive performances in healthy teenagers. Ten male adolescent athletes (mean ± SD, age = 15.4 ± 0.3 years, body-mass = 60.68 ± 5.7 kg, height = 167.9 ± 6.9 cm and BMI = 21.21 ± 2.5) performed two test sessions separated by at least one week. During each session, participants completed the Yo-Yo intermittent-recovery-test level-1 (YYIRT-1) at ~20:00 h. Then, sleep polysomnography was recorded from 22:15 min to 07:00 h, after a double blind randomized order administration of a single 10-mg tablet of MEL (MEL-10 mg) or Placebo (PLA). The following morning, Hooper wellness index was administered and the participants performed the Choice Reaction Time (CRT) test, the Zazzo test and some short-term physical exercises (YYIRT-1, vertical and horizontal Jumps (VJ; HJ), Hand grip strength (HG), and five-jump test (5-JT)). Evening total distance covered in the YYIRT-1 did not change during the two conditions (p > 0.05). Total sleep time (Δ = 24.55 mn; p < 0.001), sleep efficiency (Δ = 4.47%; p < 0.001), stage-3 sleep (N3 sleep) (Δ = 1.73%; p < 0.05) and rapid-eye-movement sleep (Δ = 2.15%; p < 0.001) were significantly higher with MEL in comparison with PLA. Moreover, sleep-onset-latency (Δ = -8.45mn; p < 0.001), total time of nocturnal awakenings after sleep-onset (NA) (Δ = -11 mn; p < 0.001), stage-1 sleep (N1 sleep) (Δ = -1.7%; p < 0.001) and stage-2 sleep (N2 sleep) (Δ = -1.9%; p < 0.05) durations were lower with MEL. The Hooper index showed a better subjective sleep quality, a decrease of the subjective perception of fatigue and a reduced level of muscle soreness with MEL. Moreover, MEL improved speed and performance but not inaccuracy during the Zazzo test. CRT was faster with MEL. Morning YYIRT-1 (Δ = 82 m; p < 0.001) and 5-JT (Δ = 0.08 m; p < 0.05) performances were significantly higher with MEL in comparison with PLA. In contrast, HG, VJ and HJ performances did not change during the two conditions (p > 0.05). The administration of a single dose of MEL-10 mg after strenuous late-evening exercise improved sleep quality and quantity, selective attention, subjective assessment of the general wellness state, and some short-term physical performances the following morning in healthy teenagers.