Date of Award


Document Type

Open Access Master's Thesis

Degree Name

Master of Science in Kinesiology (MS)

Administrative Home Department

Department of Kinesiology and Integrative Physiology

Advisor 1

Carolyn Duncan

Committee Member 1

Kevin Trewartha

Committee Member 2

Shane Mueller

Committee Member 3

Tanvi Bhatt


Introduction: Balance recovery/reactive balance prevents falls by restabilizing the center of mass (COM) when instability occurs. Dim lighting is a risk factor for falling, although limited research has examined how lighting conditions affect the ability to recover from losses of balance. The purpose of this thesis was to examine the effect of lighting conditions on reactive balance mechanisms. Methods: 20 young adults (23.3(4.4) y) completed forward lean-and-release perturbations in two lighting conditions: 1) Light: ~800 Lux; 2) Dark: 0 Lux. Optical motion capture and surface electromyography were used to quantify stepping/angular kinematics, COM control, and the timing, activation, and coordination of lower-limb neuromuscular responses. Differences between lighting conditions were analyzed with paired sample t-tests (alpha=0.05). Results: In darkness, individuals showed modified stepping (increased step length, knee flexion/extension velocity, and hip flexion velocity (pDiscussion:Balance recovery in dark environments can result in modified stepping responses and decreased COM control, which could prevent successful balance recovery in real-world environments and populations. Evidence-based lighting standards could minimize fall risk in built environments and public spaces.