The effect of benzodiazepines on exercise in healthy adult participants: A systematic review.

The use of benzodiazepines among athletes is a new and growing phenomenon according to the recent case reports published. Therefore, there is an urgent need to identify if there is rationale for the use of benzodiazepines and its effects on exercise. This review aims to provide an overview of the effects of benzodiazepine in exercise among healthy adult participants and if they might have an additional ergogenic or ergolytic effect. Electronic searches were conducted in Pubmed, Scopus and Web of Science databases up to December 2020. Search terms covered all active substance names of benzodiazepine class and search terms about sport, exercise performance and athletes. We used the Physiotherapy Evidence Database (PEDro) to assess the methodological quality of the studies included in the qualitative synthesis. The methods and planned analyses of this systematic review were pre-registered at Open Science Framework (OSF: https://osf.io/uq6j8). A total of thirty-one full articles were assessed for eligibility and ten of them were included in the qualitative analysis. We found 7 studies which investigated benzodiazepine effects after an acute dose administered, whereas only 3 studies studied long-term effects after several doses used. According to our findings it does not seem that benzodiazepines might have an ergogenic or ergolytic effect on exercise performance. The small number of articles included (n = 10) with a relatively low sample of participants (N = 16, range = 6-58) does invite us to take our results with caution. This review evidences valuable insights into the use of benzodiazepines from a physical performance point of view. Our findings highlight the unclear effects benzodiazepines might have on exercise performance and its possible mechanisms of actions. Hence, the need to conduct new studies to understand its possible effects becomes essential to protect the health of athletes of all levels.