Effects of breast motion on lower-body kinematics during running

Abstract

We measured the effects of breast motion on lower-body kinematics during overground running. Thirty female participants aged 18–60 years completed two blocks of three trials each of overground running for 25 m at self-selected pace under two conditions: with and without breast support provided by a sports bra. Participants’ body movements were analyzed with 18 parameters characterizing breast and lower-body kinematics. Sports bra use reduced breast motion and increased about 83% of the lower-body kinematic parameters, including running velocity; stride length; foot clearance; vertical and lateral center of mass displacement; and thorax, hip, knee, and ankle range of motion (all p < 0.05). Among the changed characteristics, the stride length, center of mass displacements, thorax and knee range of motions correlated negatively (r = –0.25 to –0.46) with the velocity of breast motion. Therefore, the reduction of breast motion may improve lower-body kinematics during running, which may influence sport and leisure performance.