Introduction: Introduction: to combat the COVID-19 pandemic governments have adopted measures such as quarantine and social distancing .
Objective: the main objective of the present study was to analyze the impact of COVID-19 quarantine on body mass in combat sports athletes .
Methods: we conducted a cross-sectional, prospective, multi-center study that evaluated 234 men (mean age and standard deviation, 29 ± 10 years) residing in Argentina (n = 38); Bolivia (n = 1); Brazil (n = 105); Chile (n = 30); El Salvador (n = 1); Spain (n = 22); Mexico (n = 22) and Peru (n = 15). Of these , 12 practiced Brazilian jiu-jitsu (BJJ), 54 boxing, 67 judo, 13 karate, 52 kick boxing & muay thai (KB & MT), 9 mixed martial arts (MMA), and 27 taekwondo (TKD). An online survey was created using Google Forms . It was implemented between April 4th and April 17th , 2020 . Athletes were consulted about their body mass before starting the quarantine and after 20 ± 5 days of quarantine .
Results: athletes in all combat sports were heavier during quarantine as compared to pre-quarantine (p <0.001, d = 0.12).
Conclusions: combat sports athletes experienced an increase in body mass during the COVID-19 quarantine.