Relationship between stride length and walking rate in gait training for hemiparetic stroke patients.

Sixty-three male hemiparetic patients in the recovery stage were examined to investigate the relationship between stride length and walking rate during computer-assisted gait training during a period of 4 wk. The maximum walking speed for 10 m was significantly increased from 32.3 to 53.2 m/min on average, and the stride length and walking rate also increased. However, the ratio of stride length to walking rate did not change significantly in 4 wk, with the mean value being 0.0068 m/steps/min, approximately one-half that of healthy adults based on data from previous reports. The ratio of stride length to walking rate for hemiplegic gait was invariant during the 4 wk of computer-assisted gait training, which is also true at different speeds for healthy adults. These results indicate that the maximum walking speed was significantly improved, with an invariant relationship between stride length and walking rate, and suggest that the ratio could be used as an index for gait training.

Determinants and predictors of the maximum walking speed during computer-assisted gait training in hemiparetic stroke patients.

OBJECTIVE: To investigate biomechanical determinants and predictors of walking speed in early gait training after stroke. DESIGN: Prospective. SETTING: Physical therapy room of Tohoku University Hospital. PARTICIPANTS: Thirty-four male hemiparetic stroke patients received 8 weeks of computer-assisted gait training (CAGT), which was initiated within approximately 3 months after stroke onset. MAIN OUTCOME MEASUREMENTS: The time and the number of steps required to walk 10m at the fastest possible speed (maximum walking speed [MWS]), the sway path of the center of feet pressure (CFP) in the upright posture, the change in CFP when shifting the body weight either left to right or back and forth, and the maximal isokinetic muscle strength during extension of both knees were measured at the start and at 4 and 8 weeks. Stepwise regression procedures were performed to analyze determinants and predictors of the MWS using the MWS as the dependent variable and personal characteristics, standing balance, and the muscle strength of both knees as the independent variables. RESULTS: The MWS significantly increased from 40.4 to 76.5m/min on average after 8 weeks. The determinant of MWS at the start was the postural control of shifting to the left and right (coefficient of determination of 45.4%). The determinant of MWS at 4 and 8 weeks was the muscle strength during knee extension on the affected side (coefficient of determination of 62.9% and 54.5%, respectively). The predictors of MWS at 4 weeks were the MWS at the start of CAGT, followed by muscle strength during knee extension on the affected side and the time from stroke onset to the start of CAGT (total variance of 84.3%). The predictors at 8 weeks were the MWS at the start, followed by the muscle strength during knee extension on the affected side (total variance of 73.4%). CONCLUSIONS: After 4 weeks, the biomechanical determinant of MWS had changed from the postural control of weight-shifting from left to right to the muscle strength during knee extension on the affected side. The MWS at 4 and 8 weeks could be predicted by the initial MWS, the initial muscle strength during knee extension on the affected side, and the time since stroke onset, with high coefficients of determination.