ACUTE BODY WEIGHT LOSS THROUGH DEHYDRATION AND SUDDEN DEATH METHODS IN COMBAT SPORTS: AN NARRATIVE REVIEW

Abstract

The objective was to identify the methods adopted for acute body weight (BW) loss, their consequences, and documented records of sudden death (SD) attributed to them, as well as to identify which BW reduction methods are usually adopted in different combat sports and their prevalence of use, to describe the physiological mechanisms involved in acute BW loss that may induce SD, and to document SD cases over 22 years in combat sports. This is a narrative review, conducted through searches in the PubMed^® and Scielo^® databases and through research in conventional media websites such as: https://www.espn.com; https://g1.globo.com; https://ge.globo.com; and https://www.bbc.com. The review is composed of three topics: a) to identify the BW reduction strategies usually adopted in different combat sports and their prevalence of use; b) the physiological mechanisms involved in acute BW reduction strategies; c) cases of death in fighters related to acute BW loss. The methods adopted for acute BW loss included fluid restriction, hypocaloric diets, increased physical activity, use of laxatives and diuretics, sauna or rubber suits, and vomiting. The physiological mechanisms involved in acute BW reduction strategies and associated with SD mainly include increased blood viscosity as the primary factor causing thromboembolism, as well as heart failure during fights. Cases of death in fighters related to acute BW loss were mostly observed in modalities where weigh-ins are performed days before the fight. Several types of dehydration approaches are commonly used, the most frequent being fluid restriction and increased physical activity to induce sweating, which can reduce physical and mental performance and, in extreme cases, cause death.