Ground reaction forces provide insight into how forces impact the body during walking. Kinetics deals with variables that cause specific walking patterns. Force transducers can measure muscle forces. Comparing vertical ground reaction forces in healthy and pathological gaits reveals differences due to compensations in the pathological gait. Irregularities in force signals also differentiate healthy from ataxic patients. Forces increase with speed through higher peaks and shorter durations. The stance phase makes up 60% of the gait cycle and involves heel strike, foot flat, midstance, heel rise, and toe off. Double support is when both feet contact the ground simultaneously during 12% of the cycle. Force plates measure ground reaction forces to understand how the body accelerates during