Watch where you walk: Human visual perception and motion of the lower limbs while navigating obstacles in a fatigued state

Most individuals navigate (or step up and over) obstacles on a regular basis as they walk through their environment. When they are in a physically fatigued state, this almost automatic task can become more difficult. This state can therefore lead to a higher risk of trips and falls during navigation. For example, firefighters, while carrying out job-related duties, have a higher probability of trips and falls following fatiguing physical activity compared to when they are in a rested state. Previous work has also shown that physical fatigue can lead to a decrease in visual perception of environmental objects during performance of different tasks and can change the movement patterns during ambulation. However, it is still unknown the extent to which visual perception of one’s environment and one’s movement patterns change when navigating obstacles in a fatigued state. It is important to study human visual and motor behaviors during obstacle crossing in order to better understand the general effect of fatigue on these systems. Such knowledge has direct implications for human health, especially for those in occupations that require high levels of physical activity such as firefighting, where trips and falls are the largest cause of on-the-job injury. In addition to the potential positive benefits of this knowledge can be applied to occupational health, reduction of these injuries can help to reduce the financial burden associated with worker compensation and lost work time. The central aim of this study is to examine the effect that a fatiguing simulated firefighting task has on one’s perception and movement during an obstacle navigation task. This will be addressed through two objectives:
1. Explore the role of physical fatigue on visual perception of a suddenly appearing obstacle.
2. Examine individuals’ lower-limb biomechanics during the process of obstacle navigation wen they are fatigued.