DESIGN: Overview of systematic reviews with assessment of reviews' methodological quality.
DATA SOURCES: PubMed, Web of Science, Scopus, Cochrane Database of Systematic Reviews, SPORTDiscus, ProQuest, PsycINFO and SciELO.
ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Systematic reviews with/without meta-analyses examining associations of RO with health-related indices and exercise performances in athletes and physically active individuals.
RESULTS: Fourteen systematic reviews (seven with meta-analyses) of observational studies, with low-to-critically-low methodological quality, were included. Two reviews found associations between RO and decreased sleep duration in athletes and physically active individuals. One review suggested athletes may experience more pronounced reductions in sleep duration than physically active individuals. One review found associations between RO and impaired sleep quality in athletes and physically active individuals. RO was associated with decreased energy, carbohydrate and water intake in adult-aged athletes, but not adolescents. One review suggests RO was associated with athletes' increased feelings of fatigue and decreased vigour. No association was found between RO and athletes' lean mass or haematological indices. RO was unfavourably associated with changes in athletes' performance during high-intensity exercise testing.
CONCLUSION: Continuance of training during RO could be associated with athletes' mood state disturbances, decreased sleep duration and performance decline during high-intensity exercise testing, while preserving lean mass. However, careful interpretation is necessary due to the low-to-critically-low methodological quality of the included reviews.
OBJECTIVE: This study investigated the effectiveness of the UDP in the last 6 wk of rehabilitation.
DESIGN: Pre-post study with 2-tailed paired t tests for limited a priori comparisons to examine differences.
SETTING: National Sports Institute of Malaysia.
PARTICIPANTS: 24 Malaysian national athletes.
INTERVENTIONS: 7 sessions/wk of 90 min with 3 sessions allocated for 5 or 6 UDP exercises.
MAIN OUTCOMES: Significant improvements for men and women were noted. Tests included 20-m sprint, 1-repetition-maximum single-leg press, standing long jump, single-leg sway, and a psychological questionnaire.
RESULTS: For men and women, respectively, average strength improvements of 22% (d = 0.96) and 29% (d = 1.05), sprint time of 3% (d = 1.06) and 4% (d = 0.58), and distance jumped of 4% (d = 0.59) and 6% (d = 0.47) were noted. In addition, athletes reported improved perceived confidence in their abilities. All athletes improved in each functional test except for long jump in 2 of the athletes. Mediolateral sway decreased in 18 of the 22 athletes for the injured limb.
CONCLUSION: The prevention training with UDP resulted in improved conditioning and seems to decrease mediolateral sway.
OBJECTIVE: This study aimed to report a comprehensive systematic review investigating the carryover effects of mental fatigue on skilled performance among athletes.
METHODS: A thorough search was conducted on PubMed, Web of Science, EBSCOhost (CENTRAL, SPORTDicus), and Scopus to select relevant literature, as well as on Google Scholar and sources of reference for grey literature. The selected literatures are centred on a mental fatigue protocol in which cognitive tasks are performed prior to athletic tasks. Only studies that used an experimental design to test two conditions, namely mental fatigue and non-mental fatigue, were selected.
RESULTS: Eleven articles were chosen based on the selection criteria. Mental fatigue affects skilled performance in three sports: soccer, basketball, and table tennis. A decline in skilled performance (decreased accuracy, increased performing time etc) is relevant to impaired executive functions. Seven studies focus on offensive skills, whereas only two studies are associated with defensive skills.
CONCLUSION: Mental fatigue has a negative effect on various sports skills of high-level athletes, including their technical and decision-making skills; however, the impact is greater on offensive skills than that of defensive skills in terms of the role of athletes. Impaired executive functions may be responsible for the negative effects of mental fatigue on skilled performance.
METHODS: Ten male collegiate rowers and physically active untrained subjects were recruited. Muscle synergies were extracted from 16 rowing-specific muscles using Principal Component Analysis with varimax rotation. Incremental rowing VO2 max Test was performed on slides ergometer (SE). Rowing performance and physiological variables were analyzed.
RESULTS: Rowers exerted greater power output, more energy expenditure and better rowing economy compared to untrained subjects. Rowers preferred to row slower with longer strokes compared to the untrained subjects. Three muscle synergies with high indices of similarity of waveform patterns were extracted in both groups. Significant association was found between muscle synergies and rowing economy.
CONCLUSIONS: The findings of this study showed that muscle synergies were robust during aerobic-dominant activity for collegiate rowers and untrained subjects. Rowers and coaches could utilize the findings by emphasizing on muscle coordination training, which may enhance the rowing economy.
METHODS: Thirty university badminton players aged from 19 to 22 years old were randomly divided equally into two groups, where the probiotic group (PG; n = 15) received a drink that contained Lactobacillus casei Shirota (3 × 1010 CFU) and placebo group (CG; n = 15) a placebo drink for six weeks. Anxiety, stress and mood levels were determined using the CSAI-2R, PSS and BRUMS questionnaires, respectively. Fitness levels were measured using by subjecting the players to 20-m shuttle runs (aerobic capacity), handgrips (muscular strength), vertical jumps (leg power), 40-m dash (speed) and T-test (agility). The Student's t-test (p < 0.05) was used to determine the differences between PG and CG players.
RESULTS: After six weeks, the anxiety and stress levels of PG players significantly decreased by 16% (p < 0.001) and 20% (p < 0.001), respectively, but there were no significant changes detected in CG players. Supplementation of probiotics also improved aerobic capacity in PG players by 5.9% (p < 0.001) but did not influence the speed, strength, leg power and agility.
CONCLUSIONS: Probiotics supplementation showed improved aerobic capacity and relieve anxiety and stress. However, further studies need to be carried out to determine the mechanisms through which probiotic intake produces these effects.