Optimizing Ankle Exoskeleton Assistance for Walking Across the Life Span

Not Applicable

Completed

Conditions: Aging

Registration Number: NCT04033146

Lead Sponsor: Georgia Institute of Technology

Brief Summary: The investigators seek to determine whether ankle exoskeletons can reduce metabolic energy expenditure during walking for users across the age-spectrum.

Detailed Description: Older adults walk with greater metabolic rates than young adults. Growing evidence suggests that the greater older adult metabolic rates are related to the structural properties of their lower leg tissues. The tendons of the leg of older adults are more compliant than that of young adults. Accordingly, older adult leg tendons stretch more under a given load, such as during walking, causing their muscles to operate at shorter, less optimal lengths, and higher activity levels than the muscles of young adults - a less economical way to produces force.

Thus, the investigators seek to examine whether wearing wearable robotic boots (i.e., ankle exoskeletons) could enable muscles to produce force more economically. By adding an exoskeleton in-parallel to the ankle, the investigators hypothesize that older adults will walk with lower whole-body metabolic rate than without the exoskeleton assistance.

In this study, the investigators will have both young and older adult participants walk on a treadmill with a commercially available ankle exoskeleton set in multiple assistance modes. During these trials, the investigators will measure the metabolic cost of walking in young and older adults and also take many physiological and biomechanical measurements to help assess how exoskeletons work to reduce walking effort.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 16

Inclusion Criteria

Subjects must be able to walk for 60 minutes in a 90-minute time frame.
Subjects are apparently free of cardiovascular, metabolic, and renal disease, which includes no signs or symptoms suggestive of cardiovascular, metabolic or renal disease.
Subjects have no current musculoskeletal injury.
Subjects need to be either 18-45 or 65+ years old.

These criteria meet the American College of Sports Medicine's 2015 guidelines for participant health screening prior to joining a moderate or moderate-to-vigorous exercise protocol. (Riebe et al., 2015).

Exclusion Criteria

Have dementia or an inability to give informed consent
Have a musculoskeletal injury or feel pain while walking
Have a history of dizziness and/or balance problems
Have cardiovascular, heart, metabolic, or renal disease, or respiratory problems
Smoke cigarettes
Asthma
Feel pain or discomfort in the chest, neck, jaw, arms during rest or exercise
Have orthopnea or paroxysmal nocturnal dyspnea
Have ankle edema
Have palpitations or tachycardia
Have a heart murmur
Have had a heart attack
Have diabetes
Have a pace maker
Have unusual shortness of breath with usual activities
Are <18 or 46-64 years of age
Do not speak or understand English

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
Net Metabolic Rate (Watts/kg)	3rd session, up to 2 weeks	The rate of metabolic energy that participants expend during a short walking bout in each of the experimental conditions.

Secondary Outcome Measures

Name	Time	Method

Trial Locations

Locations (1): Physiology of Wearable Robotics Laboratory (Georgia Tech)
🇺🇸
Atlanta, Georgia, United States
Physiology of Wearable Robotics Laboratory (Georgia Tech)
🇺🇸Atlanta, Georgia, United States