Vertical ground reaction force feedback to enhance stroke patients' symmetrical body-weight distribution while rising/sitting down.

A force platform with an auditory output consisting of two electronic balances was used to reinforce symmetrical body-weight distribution in stroke patients. Forty patients randomly assigned to an experimental group or a control group practised rising and sitting down for 15 min, thrice daily, 5 days a week for 6 weeks. The experimental group but not the control group received ground reaction force feedback through the auditory output. Vertical ground reaction forces under each foot were measured with two force plates. Mean difference in improvement of body weight distribution on the paretic leg was 13.2 +/- 10.7 (M, SD) per cent total body weight in the experimental group and 5.1 +/- 6.7 per cent in the control group in rising (p < 0.01) and 12.7 +/- 7.5 per cent total body weight and 4.6 +/- 6.6 per cent in sitting down tests (p < 0.001). The patients in the experimental group achieved in average close to a symmetrical body-weight distribution while rising and sitting down. Improvements in physical performance and sit-stand tests were greater in the experimental group (p < 0.05 and p < 0.01, respectively). No differences were seen in improvement in performance of activities of daily living. Symmetry in body-weight distribution in rising and sitting down correlated with high scores in physical performance, motor function in rising, and with functional ability.