Efeito do pré-condicionamento isquêmico sobre mecanismos determinantes do desempenho aeróbio em corredores de alto nível

• Ano de defesa: 2016
• Autor(a) principal: Carvalho, Jeann Lúccas de Castro Sabino de [UNIFESP]
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de São Paulo (UNIFESP)
• Palavras-chave em Português: Athletics; Ischemic preconditioning; Aerobic metabolism; Atletismo; Pré-condicionamento; Metabolismo aeróbio
• Link de acesso: https://sucupira.capes.gov.br/sucupira/public/consultas/coleta/trabalhoConclusao/viewTrabalhoConclusao.jsf?popup=true&id_trabalho=3741733; https://repositorio.unifesp.br/handle/11600/46284

Ischemic preconditioning (IPC; brief cycles of ischemia) induces protection against ischemia-reperfusion injury, which occurs due to the fact that the IPC mediates changes in the metabolism of skeletal muscles and micro and macro vascular functions. Moreover, it has been demonstrated that IPC can improve aerobic and anaerobic performance. However, the mechanisms related to this improvement remain unclear. For example, the IPC effect on maximal oxygen consumption (V? O2max) has been controversial. In part, this controversy can be attributed to lack of strict criteria to assess the V? O2max, as well as methodological flaws, such as lack or poor control of placebo and nocebo effects. Thus, limitations from previous studies were circumvented to test the effect of IPC on aerobic metabolism parameters[running oxygen cost (ROC), lactate threshold (LL) e V? O2max] and endurance performance (Tlim) in well-trained runners. Eighteen high-level athletes were submitted to three interventions in random order [IPC; false ultrasound session (PL), and control (CT)]. The athletes were informed that both IPC and the PL would improve performance compared to CT. The expected improvement of the subjects(vs. CT) was 83 and 89% for the IPC and PL, respectively. After each intervention, gas exchange, blood lactate concentration ([Lac]) and perceived exertion (RPE) were measured during a maximum incremental test. Ten minutes later, a supramaximal constant test was used to verify the V? O2max. ROC (P = 0.85), V? O2max (P = 0.68) RPE (P = 0.58), [Lac] (P = 0.65) and LL (P = 0.74) were similar among IPC, PL and CT. Time to exhaustion at supramaximal load was longer after IPC (166 ± 13 s) and PL (165 ± 13 s) than CT (143 ± 13 s; P <0.05). In summary, these results indicate that the IPC improved aerobic performance in middle and long distance runners, but the improvement was not greater than placebo. Moreover, IPC did not change LL, ROC and V̇ O2máx.