Metabolic Cost of Transport in Walking in Middle-Aged Adults Using an Ankle Exoskeleton

This study evaluated energy expenditure while walking with a powered ankle exoskeleton in middle-aged adults. Participants wore a bilateral ankle exoskeleton. Metabolic cost was measured via indirect calorimetry. Participants walked on a treadmill without the exoskeleton and with the exoskeleton unpowered, powered, and unpowered again. Net metabolic cost of transport (MCOT) was calculated. Behaviors exhibited include a decrease in MCOT, an increase in MCOT, and initial changes that diminished with time. This variability may be explained by differences in adaptation times, which may be more pronounced among middle-aged adults due to age-related changes in gait and declines in neuromuscular and sensory function. These results underscore the importance of age-related considerations in training protocols, recognizing that middle-aged adults may require longer, more structured training than young adults. Insufficient adaptation may prevent users from experiencing metabolic improvements that could contribute to reduced injury risk and lower rates of musculoskeletal disorders.