Sex- and sport-specific differences among elite strength and physique competitors

We aimed to characterize and compare elite strength athletes and physique athletes and to investigate potential sex differences and the contribution of muscle size to strength in this unique population. We examined male and female strength athletes (n=12), physique athletes (n=13) and non-trained controls (n=14). Anthropometry, maximal strength and strength endurance, and muscle cross-sectional area (ultrasound) were measured. Statistical significance was set at p<0.05. Although strength athletes excelled in their own sports, generic dynamic (leg press and arm curl one repetition maximum) or isometric knee extension torque did not differ compared to physique athletes. However, strength athletes had better muscle power in vertical jumps, while the cross-sectional area of biceps brachii was higher and body fat was lower in physique athletes. Males were more muscular and stronger, whereas females performed more repetitions in a multiple-set leg press protocol. Athletes had better strength/cross-sectional area ratios than controls only in complex tasks, but not in simple strength tasks. Partial correlation analysis with sex and training background as covariates showed that the cross-sectional area moderately explained the variance in maximal strength. In conclusion, strength athletes and physique athletes differ in sport-specific muscle size and power. In these athletes, the muscle size contributes to muscle strength. Finally, females have better strength endurance than males, independent of the training background.