Effects of a Powered Lower-Limb Exoskeleton on Walking Performance in Older Adults

Acute Effects of a Powered Lower-Limb Exoskeleton on Walking Performance in Community-Dwelling Older Adults: A Randomized Crossover Trial

The goal of this clinical trial is to learn whether a powered wearable lower-limb exoskeleton can improve walking performance in independently ambulatory older adults aged 65 to 75 years.

The main questions it aims to answer are:

• Does use of a powered lower-limb exoskeleton increase comfortable walking speed over 10 meters?
• Does use of a powered lower-limb exoskeleton increase average walking speed during a 400-meter walk?

Researchers will compare walking performance in older adults during walking with the powered exoskeleton and walking without the device to determine whether the exoskeleton improves mobility. Young-adult reference participants will also complete walking assessments to provide reference values for walking performance.

Participants will:

• Attend a screening and familiarization visit.
• Complete walking assessments with and without the powered exoskeleton in randomized order (older adults only).
• Perform a 10-meter walk test, a 400-meter walk test, and other physical performance assessments.
• Complete questionnaires about balance confidence, fear of falling, and device usability.
• Be monitored for safety events during testing.

Age-related decline in mobility is associated with reduced independence, lower quality of life, and increased risk of disability and adverse health outcomes. Walking performance is a clinically meaningful indicator of functional status in older adults, and preservation of mobility is a major goal of healthy aging. Although exercise and rehabilitation interventions can improve mobility, their benefits typically require repeated training and sustained adherence. Technologies that provide immediate assistance during walking may offer a complementary approach to supporting mobility in older adults.

Powered wearable lower-limb exoskeletons are designed to provide external mechanical assistance during locomotion. Previous studies have shown that lower-limb exoskeletons can reduce the metabolic cost of walking and improve walking performance under laboratory conditions. However, less is known about the acute effects of commercially available exoskeleton systems on clinically relevant walking outcomes in independently ambulatory older adults.

This study will evaluate the acute effects of a commercially available powered lower-limb exoskeleton on walking performance in community-dwelling older adults. The primary outcomes are comfortable gait speed during a 10-meter walk test and average walking speed during a 400-meter walk test. Secondary outcomes include lower-extremity physical performance, physiological responses during walking, perceived exertion, balance confidence, fear of falling, device usability, participant satisfaction, and safety outcomes.

The study uses a randomized crossover design. Older adult participants will complete two experimental conditions in randomized order: walking without the exoskeleton and walking with the powered exoskeleton. Participants will attend a screening and familiarization visit followed by two trial visits separated by at least 48 hours. During the familiarization visit, participants will receive device fitting and supervised practice with the exoskeleton. At each trial visit, participants will complete standardized walking and physical performance assessments under the assigned condition.

A young-adult reference group will complete no-device walking assessments to provide reference values for walking performance. Exploratory analyses will examine whether exoskeleton-assisted walking reduces the performance gap between older adults and young adults.

The study hypothesis is that use of the powered exoskeleton will improve both short-distance and sustained walking performance in older adults and partially reduce the mobility performance gap between older and young adults.

Inclusion Criteria:

• Older adults aged 65 to 75 years who are community-dwelling, independently ambulatory, able to walk independently on level ground, able to maintain standing balance without personal assistance, and able to understand study instructions.
• Young-adult reference participants aged 18 to 22 years who are healthy university students without known conditions affecting walking or balance.

Exclusion Criteria:

• Self-reported neurological disease affecting gait or balance.
• Major musculoskeletal injury or surgery affecting walking within the previous 6 months.
• Uncontrolled cardiopulmonary disease.
• Severe visual or vestibular impairment affecting safe walking.
• Current lower-limb pain that limits walking.
• Cognitive impairment that prevents informed consent or protocol adherence.
• Any condition judged by the study team to make participation unsafe.