Effect of balance support on the energy cost of walking after stroke

Abstract

Objective: To examine the influence of balance support on the energy cost of treadmill and overground walking in ambulatory patients with stroke.

Design: Cross-sectional.

Setting: Research laboratory at a rehabilitation center.

Participants: Patients with stroke depending on a walking aid in daily life (n=12; walking aid dependent ambulators) and walking aid independent ambulators (n=12), all able to walk for at least 5 minutes.

Interventions: Not applicable.

Main outcome measures: Energy cost (J·kg(-1)·m(-1)) and temporal gait parameters (walking speed, mean and coefficient of variation of stride time, and symmetry index) were obtained during 4 walking trials at preferred walking speed: overground with and without a cane and on a treadmill with and without handrail support.

Results: On the treadmill, handrail support resulted in a significant decrease in energy cost of 16%, independent of the group. Although walking aid dependent ambulators had on average a larger reduction in energy cost than walking aid independent ambulators (19% vs 14%), this interaction did not reach statistical significance (P=.11). Interestingly, overground walking with support resulted in an 8% reduction in energy cost for walking aid dependent ambulators, but a 6% increase for walking aid independent ambulators. The reduction in energy cost with support was accompanied by changes in temporal gait parameters, most notably an increase in stride time and symmetry and a decrease in stride time variability.

Conclusions: Balance support can result in a significant reduction in the energy cost of walking in stroke patients, the magnitude of which depends on walking ability and the walking task. Impaired balance control should not be overlooked as a contributing factor to the increased energy cost of walking in patients with stroke, and improving or assisting balance control should be considered to reduce the energy cost of hemiplegic gait.

Keywords: BBS; Berg Balance Scale; CV; E(gross); Energy metabolism; FAC; Functional Ambulatory Category; Gait; Postural balance; RER; Rehabilitation; SI; Stroke; TMWT; Vo(2); coefficient of variation; gross metabolic energy expenditure; oxygen consumption; respiratory exchange ratio; symmetry index; ten-meter walk test.