Efeitos do dano muscular sobre indicadores neuromusculares e de aptidão aeróbia

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) ; Processo FAPESP: 11/19656-8 ; Pós-graduação em Desenvolvimento Humano e Tecnologias - IBRC ; The aim of this study was to analyze the protective effect of a downhill running bout on running economy (RE), muscle damage and fatigue markers induced by a long-distance level running bout. Thirty healthy active males aged 23.6 ± 3.9 years, weight 73.8 ± 10.2 kg, height of 174.3 ± 6.8 cm and body mass index 24.2 ± 3.1 kg.m2 took part on the study and were randomically divided into experimental (GEXP) and control (GCON) groups. Their maximal oxygen consumption ( O2max) and lactate threshold (LT) were determined by incremental test until exhaustion. Fatigue indexes (isometric peak torque - IPT), electromyographic signal (root mean square during the IPT - RMSipt), rate of force development (RFD) of the rectus femoris and vastus lateralis (knee extensors), biceps femoris (BF) and semitendinous (knee flexors), muscle damage markers (creatine quinase - CK) and RE were assessed before, immediately after and 48 hours after a first long-distance running bout (R1) (60 min at 70% O2max). On the following week, volunteers of the GEXP performed a downhill running bout (30 min at 70% O2max with a -15% slope) to induce muscle damage (MD) with all aforementioned variables being assessed at the same time points of the condition R1. Fourteen days after the downhill running bout a second long-distance run (R2) was performed, repeating the same assessment protocol. The GCON group did not perform the downhill running bout. However, the GCON performed the same procedures of GEXP, 21 days after R1. The variables were compared by analysis of variance (ANOVA-F) for repeated measures, with the significance level set as p < 0.05. On the long-distance runs (R1 and R2), significant differences over time (decrease in pre vs. post; increase in post vs. 48 h) for IPT of the knee extensors and knee flexors, and RFD of the knee extensors were found, irrespectively of the run or group. ...