Conflicting adaptations have been observed when strength and endurance training are combined (Hickson 1980), which has been attributed to a high intensity and volume of training and as well as training modes (Wilson et al. 2011). Acute responses to the order of exercise in a single session has not been thoroughly investigated, thus this study examined the acute responses and recovery of force production and serum hormone concentrations to single-session combined strength (S) and endurance (E) loadings in which the order of exercises is randomized. METHODS Twenty-two recreationally endurance trained subjects 10 women (W) and 12 men (M) (36±8 years) completed two loadings [S followed by E (SE) and E followed by S (ES)]. The S loading focused on the leg extensors including maximal and explosive exercises while E consisted of moderate intensity running for 60min. Maximal isometric force (MVC), countermovement jump (CMJ) and serum hormone concentrations (total testosterone, T and cortisol, C) were measured pre, mid, and post loadings as well as at 24h and 48h of recovery. RESULTS Significant decreases were observed in MVC of M at mid and post in both ES (p<0.05) and SE (p<0.001). In W, a significant decrease in MVC was observed at mid only in SE (p<0.01) and at post in both ES (p<0.01) and SE (p<0.05). MVC remained decreased in M at 24h and 48h in both ES and SE (p<0.01-0.09) but recovered in W. A significant decrease in CMJ height was observed in M after S in both loadings. CMJ height did not change during the loadings in W, but was significantly decreased at 24h and 48h of recovery after ES. T concentrations did not change significantly over time in M or W during SE or ES; however, in M (the increase in) concentration of T was significantly higher in ES than in SE at 24h and 48h (p<0.05). C concentrations did not change significantly over time in M, but were slightly higher (p=0.072) in M following SE than ES. Concentrations of C in W decreased during the loadings but were statistically unaltered during recovery. DISCUSSION The present combined S and E loadings induced more decreases in MVC and CMJ height and greater hormonal responses in M than in W. The present ES and SE loadings produced differing neuromuscular and hormonal responses suggesting that the order of concurrent S and E exercise has an influence on acute physiological responses. These findings may have important implications for training in recreational endurance athletes.
© Copyright 2012 17th Annual Congress of the European College of Sport Science (ECSS), Bruges, 4. -7. July 2012. Veröffentlicht von Vrije Universiteit Brussel. Alle Rechte vorbehalten.