Gender differences in the control of the upper body accelerations during level walking

In young individuals, the oscillations of the upper body during level walking are characterised by an attenuation of the linear acceleration going from pelvis to head level. The mechanisms through which the three components of the head acceleration are controlled during level walking have been recently investigated in the literature, but, to our knowledge, gender differences have not been taken into account. The aim of this study is to test whether this omission could lead to erroneous conclusions. Two groups of young healthy volunteers (10 males and 10 females, respectively) were asked to walk on a linear pathway and the accelerations of the upper body were measured using wearable inertial and magnetic sensors located at pelvis, shoulder, and head levels, respectively. Both groups managed to attenuate the upper body anteroposterior accelerations, with a more effective shoulder to head attenuation for the women group. In the medio-lateral direction, the results were quite different in the two groups. Not only the male subjects did not manage to attenuate the accelerations in the upper body as much as the females did, but in the male group the accelerations at head level were even increased with respect to those at shoulder level. The ability of the female group to implement a more effective shoulder to head attenuation allowed them to reach the same resultant head acceleration of the male group, even though the females had more accelerated pelvis movements. Despite further investigation is needed to provide an explanation for these gender differences, the results of this study show that these differences should be taken into account when analysing upper body movements during walking.