TY - JOUR ID - 4055597 TI - The magnitude of rapid weight loss and rapid weight gain in combat sport athletes preparing for competition: A systematic review SP - 441-452 JF - International Journal of Sport Nutrition and Exercise Metabolism T2 - International Journal of Sport Nutrition and Exercise Metabolism VL - 29 IS - 4 AU - Matthews, J. J. AU - Stanhope, E. N. AU - Godwin, M. S. AU - Holmes, M. E. J. AU - Artioli, G. G. PY - 2019 LA - English M3 - biological and medical sciences M3 - combat sports KW - combat sport KW - boxing KW - judo KW - wrestling KW - taekwondo KW - karate KW - body KW - body indices KW - weight KW - regulation KW - competition KW - method SN - 1526-484X AB - Combat sport athletes typically engage in a process called making weight, characterized by rapid weight loss (RWL) and subsequent rapid weight gain (RWG) in the days preceding competition. These practices differ across each sport, but no systematic comparison of the size of the changes in body mass exists. The aim was to determine the magnitude of RWL and RWG in combat sport athletes preparing for competition. The review protocol was preregistered with PROSPERO (CRD42017055279). In eligible studies, athletes prepared habitually with a RWL period =7 days preceding competition. An electronic search of EBSCOhost (CINAHL Plus, MEDLINE, and SPORTDiscus) and PubMed Central was performed up to July 2018. Sixteen full-text studies (total 4,432 participants; 156 females and 4,276 males) were included, providing data from five combat sports (boxing, judo, mixed martial arts, taekwondo, and wrestling). Three studies reported RWL and 14 studies reported RWG. Duration permitted for RWG ranged 3-32 hr. The largest changes in body mass occurred in two separate mixed martial arts cohorts (RWL: 7.4 ± 1.1 kg [~10%] and RWG: 7.4 ± 2.8 kg [11.7% ± 4.7%]). The magnitude of RWG appears to be influenced by the type of sport, competition structure, and recovery duration permitted. A cause for concern is the lack of objective data quantifying the magnitude of RWL. There is insufficient evidence to substantiate the use of RWG as a proxy for RWL, and little data are available in females. By engaging in RWG, athletes are able to exploit the rules to compete up to three weight categories higher than at the official weigh-in. UR - https://doi.org/10.1123/ijsnem.2018-0165 DO - 10.1123/ijsnem.2018-0165 ER -