BIOMECHANICAL AND MUSCULOSKELETAL CHANGES IN PREGNANT RUNNERS FROM THE 3RD TRIMESTER TO 3 MONTHS POSTPARTUM

PURPOSE: There are many studies on running kinematics for the general population, however few studies have investigated runners throughout their pregnancy. As strength and range of motion may also play a role, it is important to investigate what changes may occur to the musculoskeletal system. The purpose of this study was to understand the biomechanical and musculoskeletal changes that may occur through 3rd trimester to 3 months postpartum. METHODS: Range of motion testing was measured with an inclinometer and repeated 3 times for each movement. Participants ran on a treadmill at their self-selected, comfortable 5 K pace. Once this pace was reached, two, 30s running trials were recorded using a 3D motion analysis system. Data from 15 foot-strikes were collected and kinematic variables were processed. Strength was assessed with a stationary dynamometer and participants completed 5 s maximal contraction with a 10s rest 3 times for all motions at the hip (flexion/extension, internal rotation/external rotation, abduction/adduction). RESULTS: 4 runners were assessed at all time points. From 3rd trimester to 3 months postpartum, there was no change in running peak joint angles during the stance phase at the hip, knee and ankles. There were no statistically significant changes between the 3rd trimester and 3 months postpartum for range of motion measurements (Figure below). Hip strength did not change statistically between 3rd trimester and 3 months postpartum. CONCLUSION: Although the body may go through many physical changes during pregnancy, there were no statistically significant changes in the running biomechanics, strength, or range of motion between the 3rd trimester and 3 months postpartum in this small pilot study. Future studies should recruit larger sample sizes to continue to investigate if running strength, motion and mechanical changes are significant between the 3rd trimester and 3 months postpartum as well as investigate the entire perinatal period. APTA Pelvic Health