Effects of acute passive stretching on mean response time during an incremental ramp test

The effects of stretching administration on aerobic performance have not been yet extensively investigated. This study aims to assess the acute effects of pre-exercise passive stretching on the mean response time (MRT), i.e., the temporal interval between the increase in work rate and the rise in pulmonary oxygen uptake (\( \dot{V}\hbox{O}_{2 } \)), during an incremental ramp test. Eight physically active males (age 23 ± 4 years; stature 1.74 ± 0.13 m; body mass 71 ± 7 kg; mean ± standard deviation) performed two incremental ramp tests (25 W/min) of 5 min, with and without pre-exercise stretching. During tests, we measured \( \dot{V}\hbox{O}_{2 } \) and other metabolic and cardiorespiratory parameters. Before and after stretching the joint mobility and maximum voluntary contraction (MVC) of the knee extensor muscles were evaluated. Stretching reduced MVC by 9 % (P < 0.05) and lengthened MRT by 34 % (P < 0.05). These results are compatible with an altered motor unit activation pattern due to mechanical and neuromuscular changes of the muscle-tendon unit induced by stretching, which lead to an altered aerobic response to ramp exercise.