Trial design: Double-blind, counter-balanced, crossover trials were conducted to examine whether tennis performance was affected during menstruation, with and without dehydroepiandrosterone sulfate (DHEA-S) supplementation.
Methods: Ten Division 1 collegiate tennis players (aged 18-22 years) were evenly assigned into placebo-supplemented and DHEA-supplemented (25 mg/day) trials. Treatments were exchanged among the participants after a 28-day washout. Tennis serve performance was assessed on the first day of menstrual bleeding (day 0/28) and on days 7, 14 and 21.
Results: Mood state was unaltered during the menstrual cycles in both trials. The lowest tennis serve performance score (speed times accuracy) occurred on day 14 (P=0.06 vs day 0; P=0.01 vs day 21) in both placebo and DHEA trials. Decreased performance on day 14 was explained by decreased accuracy (P=0.03 vs day 0/28; P=0.01 vs day 21), but not velocity itself. Isometric hip strength, but not quadriceps strength, was moderately lower on day 14 (P=0.08). Increasing plasma DHEA-S (by ~65%) during the DHEA-supplemented trial had no effects on mood state, sleep quality or tennis serve performance.
Conclusion: We have shown that menses does not affect serve performance of collegiate tennis players. However, the observed decrement in the accuracy of serve speed near ovulation warrants further investigation.
METHODS AND ANALYSIS: We aim to conduct a review of reviews (RoR) to identify, evaluate and synthesise all systematic reviews (SRs) of workplace interventions aimed at reducing SB and/or promoting PA among adults. Systematic searches for relevant SRs will be conducted in six databases: Cochrane Systematic Review Database, Cumulative Index to Nursing & Allied Health Literature through EBSCOhost, EMBASE, PubMed including MEDLINE, Scopus and Web of Science. Selection for final inclusion and data extraction will be performed by two independent reviewers. SRs will be included if they assessed interventions aimed at reducing SB or promoting PA in the workplace, and if they report on changes in the respective behavioural outcomes in the occupational domain.
DISCUSSION: This RoR will be valuable to policy-makers and employers who are looking for strategies to promote health at work. This will also allow potential research gaps to be identified, so that the design of future studies can be better informed.
TRIAL REGISTERATION: This study has been registered with the PROSPERO International Prospective Register of Systematic Reviews (registration number CRD42020171774).