Influence of gender and muscle architecture asymmetry on jump and sprint performance.

Muscle architecture is a determinant for sprinting speed and jumping power, which may be related to anaerobic sports performance. In the present investigation, the relationships between peak (PVJP) and mean (MVJP) vertical jump power, 30m maximal sprinting speed (30M), and muscle architecture were examined in 28 college-aged, recreationally-active men (n = 14; 24.3 ± 2.2y; 89.1 ± 9.3kg; 1.80 ± 0.07 m) and women (n = 14; 21.5 ± 1.7y; 65.2 ± 12.4kg; 1.63 ± 0.08 m). Ultrasound measures of muscle thickness (MT), pennation angle (PNG), cross-sectional area (CSA), and echo intensity (ECHO) were collected from the rectus femoris (RF) and vastus lateralis (VL) of both legs; fascicle length (FL) was estimated from MT and PNG. Men possessed lower ECHO, greater muscle size (MT & CSA), were faster, and were more powerful (PVJP & MVJP) than women. Stepwise regression indicated that muscle size and quality influenced speed and power in men. In women, vastus lateralis asymmetry negatively affected PVJP (MT: r = -0.73; FL: r = -0.60) and MVJP (MT: r = -0.76; FL: r = -0.64), while asymmetrical ECHO (VL) and FL (RF) positively influenced MVJP (r = 0.55) and 30M (r = 0.57), respectively. Thigh muscle architecture appears to influence jumping power and sprinting speed, though the effect may vary by gender in recreationally-active adults. Appropriate assessment of these ultrasound variables in men and women prior to training may provide a more specific exercise prescription. Key pointsThe manner in which thigh muscle architecture affects jumping power and sprinting speed varies by gender.In men, performance is influenced by the magnitude of muscle size and architecture.In women, asymmetrical muscle size and architectural asymmetry significantly influence performance.To develop effective and precise exercise prescription for the improvement of jumping power and/or sprinting speed, muscle architecture assessment prior to the onset of a training program is advised.