Effects of walking velocity on vertical head and body movements during locomotion

Abstract

Trunk and head movements were characterized over a wide range of walking speeds to determine the relationship between stride length, stepping frequency, vertical head translation, pitch rotation of the head, and pitch trunk rotation as a function of gait velocity. Subjects (26-44 years old) walked on a linear treadmill at velocities of 0.6-2.2 m/s. The head and trunk were modeled as rigid bodies, and rotation and translation were determined using a video-based motion analysis system. At walking speeds up to 1.2 m/s there was little head pitch movement in space, and the head pitch relative to the trunk was compensatory for trunk pitch. As walking velocity increased, trunk pitch remained approximately invariant, but a significant head translation developed. This head translation induced compensatory head pitch in space, which tended to point the head at a fixed point in front of the subject that remained approximately invariant with regard to walking speed. The predominant frequency of head translation and rotation was restricted to a narrow range from 1.4 Hz at 0.6 m/s to 2.5 Hz at 2.2 m/s. Within the range of 0.8-1.8 m/s, subjects tended to increase their stride length rather than step frequency to walk faster, maintaining the predominant frequency of head movement at close to 2.0 Hz. At walking speeds above 1.2 m/s, head pitch in space was highly coherent with, and compensatory for, vertical head translation. In the range 1.2-1.8 m/s, the power spectrum of vertical head translation was the most highly tuned, and the relationship between walking speed and head and trunk movements was the most linear. We define this as an optimal range of walking velocity with regard to head-trunk coordination. The coordination of head and trunk movement was less coherent at walking velocities below 1.2 m/s and above 1.8 m/s. These results suggest that two mechanisms are utilized to maintain a stable head fixation distance over the optimal range of walking velocities. The relative contribution of each mechanism to head orientation depends on the frequency of head movement and consequently on walking velocity. From consideration of the frequency characteristics of the compensatory head pitch, we infer that compensatory head pitch movements may be produced predominantly by the angular vestibulocollic reflex (aVCR) at low walking speeds and by the linear vestibulocollic reflex (1VCR) at the higher speeds.

Influence of Ambient Music on Perceived Exertion During a Pulmonary Rehabilitation Session: A Randomized Crossover Study

“…Choice of music tempo is important. A tempo of 120 beats/min is the tempo spontaneously adopted by people during an exercise such as walking 47 or while performing usual daily activities. 48 On a treadmill, this tempo is optimal for slow walking.…”

“…48 On a treadmill, this tempo is optimal for slow walking. 47 Moreover, it is the more prevalent tempo in a sample of 74,042 pieces of modern music. 49 To avoid the demonstrated influence of loudness on treadmill exercise, 50 the sound level was fixed for all experiments.…”

Using Head Tracking Data for Robust Short Term Path Prediction of Human Locomotion

“…A further disturbing effect for prediction is that the movement of the body during walking is not necessarily aligned with the intended walking direction. A tracking system that is mounted on the user's head, will also measure movements to the side as well as up and down due to the mechanisms of the human gait [22,23]. Thus, the effects of noise and gait oscillations have to be filtered out in order to achieve a reliable prediction of the intended walking direction.…”

Full scaled 3D visual odometry from a single wearable omnidirectional camera

“…1). An induced effect of human walking is a head vertical oscillation whose frequency matches up with the step frequency [10]. Our work is based on the premise that if the 6 d.o.f.…”