The Acute Effects of Antagonist Stretching on Agonist Movement Economy

Current research on the effects of stretching on movement performance varies. However, these studies focused on stretching agonist and antagonist muscle responsible for movement production. Few studies investigated the influence of antagonist stretching on exercise performance. The purpose of this study is to examine the acute effects of antagonist stretching on agonist movement economy. 14 participants (5 male, 9 females; 168.32 ± 7.63 cm stature; 65.00 ± 7.28 kg mass) completed baseline active ROM (AROM) and passive ROM (PROM) measurements. The experimental design required participants to complete two 5 min trials of seated hip abduction movement, one pre-stretching and one post-stretching (criterion >15% PROM). Each trial required participants to abduct (and adduct) both legs to 90% of AROM repeatedly for 5 min. The task was performed with no external resistance, only dependent upon the ability of agonist to perform the movement, while overcoming the resistance of the antagonist musculature. Principles of indirect calorimetry were used to calculate energy expenditure (kJ•min^-1). Paired t-tests compared energy expenditure of the stretching and non-stretching trials. A greater PROM in post-stretching than pre-stretching was observed with an increase in PROM of 21.6±4.5° (p<0.001). There was also greater AROM in post-than pre-stretching with an increase in of 11.3± 9.2° (p<0.001). Less energy was expended during post-compared to pre-stretching exercise, with a decrease in EE of 0.66 ± 1.17kJ•min^-1 (p<0.05). Increasing antagonist ROM by stretching resulted in a decrease in agonist energy expenditure and may be a viable mechanism to increase athletic performance.