Reduction in energy expenditure during walking using an automated stride assistance device in healthy young adults.

ABSTRACT

OBJECTIVE: To investigate the effects of an automated stride assistance device that assists hip joint flexion and extension movement in energy expenditure during walking in healthy young adults using an expired gas method. DESIGN: Prospective, single-group design to compare the differences of energy expenditure between 2 assistive conditions. SETTING: Laboratory. PARTICIPANTS: Healthy volunteers (N=10) aged 21 to 32 years. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Oxygen consumption per unit time (V˙o2) cost (ml·kg(-1)·m(-1)), and heart rate (beats/min) were measured in 2 assistive conditions (with 3-Nm hip motion assistance and without assistance) and at 2 walking speeds (comfortable walking speed [CWS] and maximum walking speed [MWS]). RESULTS: There were no significant differences in walking speed between the with- and without-assistance conditions at either the CWS or MWS. The V˙o2 cost and heart rate were significantly reduced in the with-assistance condition compared with the without-assistance condition, at both the CWS and MWS. The reduction in the V˙o2 cost during the with-assistance condition, relative to the without-assistance condition, was 7.06% at the CWS and 10.52% at the MWS. CONCLUSIONS: The automated stride assistance device is useful for reducing energy expenditure during walking in healthy adults. Further studies are warranted to investigate if this device provides substantial help to individuals with impaired mobility as a result of strength deficits.