Effect of age on characteristics of forward and backward gait at preferred and accelerated walking speed.

BACKGROUND Backward walking is used increasingly in rehabilitation programs to promote balance, strength, and aerobic conditioning. This study examines the effect of movement direction on the temporal-spatial gait characteristics of old versus young adults when progressing at a comfortable pace and as fast as possible. METHODS Participants included 40 old (mean age 77.7, standard deviation +/- 6.2) and 30 young volunteers (mean age 24.0, standard deviation +/- 2.3), who were independent walkers. Using a computer-based walkway system, participants were requested to walk forward and backward at a normal pace and as fast as possible. Analyses of variance and Tukey-Kramer tests were conducted to determine effects of age, movement direction, and acceleration of gait speed on various gait parameters. RESULTS Forward and backward walking of elderly persons is generally characterized by a lower velocity, cadence, stride length, and swing phase, accompanied by an increase in the double-support phase. Reversing from forward to backward walking presents a similar pattern in both age groups, with a decrease in gait velocity, stride length, and swing phase, an increase in the double-support phase, and no change in cadence. However, the decrease in stride length is significantly greater among elderly persons. In young persons, higher gait velocities are achieved by concurrent increases in stride length and cadence, regardless of movement direction. Ability of older persons to increase backward ambulation is limited and relies solely on increasing cadence. CONCLUSIONS Elderly persons demonstrate difficulties in walking backward, with stride length particularly affected. These difficulties must be considered when using backward ambulation for rehabilitation of elderly persons.