Trunk and lower limb muscularity in sprinters: what are the specific muscles for superior sprint performance?

Absolute and relative CSAs of most trunk and lower limb muscles, including the psoas major (PM) and gluteus maximus (GM), were significantly larger in sprinters than in non-sprinters (all P < 0.001, d = 0.91 to 1.82). The absolute and relative CSAs of the PM and GM correlated significantly with personal best 100-m sprint time in sprinters (r =  - 0.363 to - 0.388, all P < 0.01). A stepwise multiple regression analysis revealed that both CSAs of absolute PM and relative GM were predictive variables for the personal best 100 m sprint time in sprinters (β =  - 0.289 and - 0.287, respectively, both P < 0.05). These findings suggest that the PM and GM may be specific muscles for superior sprint performance in sprinters.