The goal of this pilot study is to test the protocol for investigating the longer-term effects of torso weighting on physical activity, number of falls, and muscle activation (when muscles turn on and off and how intensely) in five volunteers with multiple sclerosis. The hypotheses of this study include: torso weighting will (1) increase physical activity, (2) decrease the number of falls, and (3) improve the timing and coordination of muscle activation during balance perturbations.