Case Report: Effects of a simulated jiu-jitsu fight on hematological, biochemical, and electrolyte responses in athletes with transfemoral amputation: a multiple-case study.

BACKGROUND: Blood tests are commonly performed in sporting contexts to screen for possible medical conditions associated with physical performance. This study aimed to: i) investigate the effects of jiu-jitsu fighting on cell damage; and ii) monitor acute hematological patterns. METHODS: Blood samples were collected from three middle-aged men, with transfemoral amputation, practitioners of jiu-jitsu parasport at a professional level, before and after a simulated fight, to screen for possible medical conditions that could compromise performance and cause sports injuries. Ethical aspects were respected. The following analyses were performed: blood count, markers of muscle damage, electrolytes, and analysis of iron stores. RESULTS: Ferritin levels were above reference values for two participants, even before the simulated fight. Urea and creatinine were within reference values. The other hematological variables also increased, but remained within the reference limits considered normal. Electrolyte concentrations (Na, K, Cl -, and Mg) showed significant changes in K and Mg after the simulated fight (p < 0.05). Significant increases were also observed for lactate and LDH (p < 0.05). CONCLUSIONS: It is concluded that the simulated fight led to alterations in all observed parameters, even though the majority of values remained within limits considered normal.