Sex-differences in counter movement jump kinetics and kinematics following 10-week marine officer candidates school

The Counter Movement Jump (CMJ) is a field expedient test to evaluate kinetics and kinematics relating to readiness, and injury risk. There is a greater incidence of injuries in women during military training and understanding key measures within the CMJ between sexes may be useful in determining injury/performance differences. PURPOSE: To evaluate sex differences in performance, kinetic and kinematic variables for the CMJ in Marine Officer Candidates (MOC) pre and post Officer Candidates School (OCS). METHODS: 375 MOCs (women n=72, 25±3 y, 65.9±7.1 kg, 164.9±5.7 cm; men n=303, 25±3 y, 81.3±9.4 kg, 177.5±6.9 cm) performed three maximal CMJs, 15 second rest between CMJs, on Hawkin Dynamics force plate (FP) and DARI marker less motion capture (mMoCap) pre and post 10-weeks of OCS, a rigorous graded physical, leadership and academic training pipeline for incoming Marine Officers. Three CMJs were averaged to one jump, and right and left limbs were averaged for mMoCAP. Separate 2-way mixed measures ANOVAs (Time*Sex) were conducted on each CMJ dependent variable 1) FP: avg. propulsive force (APF), avg. braking force (ABF), jump height (JH) 2) mMoCap: loading hip flexion (LHF), loading knee flexion (LKF), loading ankle flexion (LAF). RESULTS: There was a significant interaction effect on JH (p=