Upper extremity kinematics during walking gait changes through pregnancy

Thirty percent of adults in the United States use wearable fitness devices as of 2020 [1], such as fitness watches, to monitor and track health and physical activity parameters. Physical changes during pregnancy may impact wrist worn device accuracy. The arms may be needed as compensation during walking because thorax axial rotation may be inhibited by pelvic tilt during pregnancy [2]. To examine arm motion changes, twenty-three pregnant women (28 ± 4 y) were tested in four-week intervals ( ± 2 weeks) at 18-, 22-, 26-, 30- and 34-weeks’ gestation. Kinematic data were measured during self-selected speed walking. Segment angles and angular velocities were analyzed over time. Linear regressions were used to analyze the correlations between arm motion and the other kinematic variables. Arm range of motion significantly increased (p = 0.006) over gestation, but leg, thorax, and pelvis range of motions did not significantly change. Arm range of motion was correlated with pelvis (r2 =0.311, p = 0.001, β = 1.724) and leg (r2 = 0.285, p = 0.004, β = 1.520) range of motion and gait velocity (r2 =0.566, p = 0.001, β = 39.110). Arm velocities significantly increased (p