Speed and temporal-distance adaptations during treadmill and overground walking following stroke

Objective. To compare the maximum gait speed of stroke subjects attained during treadmill and overground in stroke subjects and to identify the temporal-distance determinants of the maximal gait speed. Methods. Ten individuals with hemiparetic gait deficits and whose walking speeds ranged between 0.24 m/s and 0.82 m/s participated. Five healthy age-matched controls were also tested to provide comparative data for the gait speed transfer between the 2 modes of locomotion. Following a brief habituation process to walking on the treadmill, subjects were tested while walking at comfortable and maximal speeds on the treadmill and overground, in a random order. Main Outcome Measure. Self-selected comfortable and maximum gait speed and temporal distance factors were acquired using a 6-camera Vicon (TM) motion analysis system and compared between treadmill and overground walking at a similar speed. Results. Overground walking resulted in higher maximal speeds (P < 0.001), greaterstride lengths (P < 0.001), and a lower cadence (P < 0.02), as compared to treadmill. The comfortable gait speed and the maximum stride length proved to be strong determinants for the maximal speed on both modes of locomotion (P < 0.01), but the maximum cadence was correlated to maximum speed only for overground locomotion (P < 0.05). Conclusions. Stroke subjects walked slower on the treadmill as compared to overground. They also used a different strategy to increase gait speed, relying mostly on increasing the stride length during treadmill ambulation.