This study is not new, but we can apply the findings to our interventions for the elderly and those suffering from Parkinson’s disease. The authors built on the existing knowledge of how two parameters – center of pressure and center of mass – allow for the taking of the first step. They compared the initiation of gait in healthy young subjects to that of elderly subjects and subjects with Parkinson’s disease. The measured variables were the center of pressure (COP) from a force plate under each foot, center of mass (COM) from motions of the body segments, and electromyography recording (EMG) of the muscles. Their results showed the same pattern in the elderly and Parkinson’s patients, but the shift of the COP (and the resulting drive of the COM) was reduced. The COP-COM movement was less in the elderly compared to the young subjects, and less in the Parkinson’s subjects compared to the elderly.