Gender Differences in Leg Stiffness and Stiffness Recruitment Strategy During Two-Legged Hopping

Abstract

The authors compared leg stiffness (K_VERT), muscle activation, and joint movement patterns between 11 men and 10 women during hopping. Physically active and healthy men and women performed continuous 2-legged hopping at their preferred rate and at 3.0 Hz. Compared with men, women demonstrated decreased K_VERT; however, after the authors normalized for body mass, gender differences in K_VERT were eliminated. In comparison with men, women also demonstrated increased quadriceps and soleus activity, as well as greater quadriceps-to-hamstrings coactivation ratios. There were no significant gender differences for joint movement patterns (p >.05). The relationship between the observed gender differences in muscle recruitment and the increased risk of anterior cruciate ligament injury in women requires further study.

Keywords:

• ACL
• quadriceps
• coactivation
• hop
• jump