Soft Hip Exoskeleton Reduces Physiological Cost and Perceived Exertion In Older Adults During Uphill Walking
June 9th, 2026
This protocol evaluates the efficacy of a lightweight soft hip exoskeleton in reducing physiological stress during uphill walking in older adults. Using a randomized crossover design, the method demonstrates that the device significantly reduces physiological cost and subjective fatigue in the elderly.
We test if our soft hip exoskeleton reduce physiological cost and fatigue in older adults walking uphill. Traditional rigid exoskeleton are too heavy, but our soft hip device is often lightweight and definitely help. To begin, explain the study procedures to a participant aged 60 to 75 years and confirm that they can walk independently on a treadmill for at least 15 minutes.
Set the treadmill parameters to 3.5 kilometers per hour and a 15%incline. Attach a magnetic safety lanyard from the participant's belt to the treadmill autostop switch and keep a supervising researcher within continuous reach of the manual emergency stop button. Prepare the exoskeleton device before testing.
Verify that the battery charge level is greater than 90%Manually inspect the drive units to confirm the absence of cable entanglement, mechanical binding, or excessive friction in the transmission mechanisms. Configure the exoskeleton to operate in the terrain-adaptive climbing, downhill, and flat modes with five assistance levels providing up to 18 newton meters of torque. In the climbing mode, enable the gait learning algorithm and angle-triggered mechanism within the zero to 90-degree range to synchronize hip flexion assistance with the participant's gait cycle.
Personalize the assistance magnitude predominantly at levels three or four based on participantive tolerance during adaptation. Attach a heart rate monitor to the participant for continuous data recording. Print the Borg rating of perceived exertion scale from 6 to 20 and the visual analog pain scale from 0 to 10 on A4 paper.
Position the printed scales within the participant's line of sight for easy access during testing. Check the participant's height to select the appropriate device size. Select size L for a height greater than 165 centimeters and size M for a height less than or equal to 165 centimeters.
Assist the participant in donning the shoulder straps. Adjust the back module height so that the lateral hip motor units align with the participant's greater trochanter and fasten the magnetic waist buckle. Tighten the lateral adjustment straps above the iliac crest to anchor the device securely to the pelvis and prevent slippage.
To secure the leg connection, align the thigh struts approximately 5 to 10 centimeters above the patella. Secure the hooks and rotate the Boa dial clockwise to tighten the thigh straps. Verify proper strap tension by ensuring approximately 1 to 1.5 centimeters of clearance when the strap is pulled away from the skin.
Have the participant perform squats and high leg lifts to confirm there is no mechanical interference or excessive cable tension. For the 15-minute adaptation session, remove the device and ask the participant to walk on the treadmill at 3.5 kilometers per hour and a 15%incline for five minutes. Next, have the participant walk with the unpowered exoskeleton for five minutes.
Then, turn on the device and let the participant walk with the powered exoskeleton for five minutes while gradually increasing the assistance intensity from setting one to their preferred comfort level. After adaptation, have the participant rest in a seated position for 20 minutes before the formal trials to ensure that heart rate and perceived exertion return to baseline. Cover all light-emitting diode indicators including power and mode lights with electrical tape to maintain visual blinding.
Randomize the order of the three experimental conditions. In the no-exo condition, have the participant walk in standard sportswear without the exoskeleton. In the exo-on condition, activate the device in climbing mode with the assist intensity set to level three or four.
Adjust the assistance level until the participant shows a stable gait pattern without postural instability, compensatory movements, or discomfort. Provide a 40-minute seated rest period between trials to allow heart rate and fatigue levels to return to baseline. Have the participant walk naturally on the treadmill for 15 minutes without holding the handrails unless required for safety.
Continuously record heart rate during the task. Average the data collected between minutes 12 and 15 at a sampling rate of one hertz to calculate the steady-state heart rate. Define the absolute highest rate recorded during the task as the peak heart rate.
At minute 14, ask the participant to report the level of exertion using the Borg rating of perceived exertion scale. Immediately after the task, visually inspect the skin contact areas for erythema, blisters, or pressure marks. Record joint pain using a 0 to 10 centimeter visual analog scale where 0 indicates no pain and 10 indicates the worst imaginable pain.
Classify scores greater than or equal to four as clinically significant discomfort requiring further evaluation. Finally, calculate the physiological cost index by subtracting resting heart rate from walking heart rate and dividing the result by walking speed. A total of 20 healthy older adults, including 10 male and 10 female participants, completed all three walking conditions without any reported adverse events.
The exo-on condition resulted in a significantly lower physiological cost index than the no-exo condition and the exo-off condition. The no-exo index was also significantly lower than exo-off. Exploratory paired comparisons showed lower peak heart rates in the exo-on condition than the no-exo and exo-off conditions.
Subjective fatigue measured by the Borg rating of perceived exertion scale was significantly lower in exo-on than in exo-off, but was not significantly different from no-exo. The protocol evaluates physiological cost and the muscle fatigue during uphill walking. The main challenge is putting the device on right and choosing the best fit for blends.
Future studies can test real-world outdoor hills and including a larger group of device patients.
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Overview
This study evaluates the effectiveness of a lightweight soft hip exoskeleton in reducing physiological strain and perceived exertion during simulated mountaineering in older adults. Through a randomized crossover trial, the research investigates whether such assistive technology can support safer and more efficient physical activity for this population.
Key Study Components
Area of Science
- Exercise Physiology
- Gerontology
- Biomechanics
Background
- Mountain hiking and mountaineering are popular among active older adults for cardiovascular fitness.
- These activities can accelerate neuromuscular fatigue, increasing the risk of falls and musculoskeletal injuries.
- Wearable assistive devices, such as soft exoskeletons, may help mitigate these risks.
- Understanding the physiological impact of such devices is crucial for promoting safe physical activity in aging populations.
Purpose of Study
- To determine if a soft hip exoskeleton can reduce physiological and perceived exertion during uphill walking in older adults.
- To assess whether the device offsets its own mass and provides a net benefit in cardiovascular effort.
- To compare active, passive, and no-exoskeleton conditions in a controlled setting.
Methods Used
- Randomized crossover trial with twenty healthy older adults (average age 63.45 years).
- Participants walked on a treadmill at a 15% incline and 3.5 km/h for 15 minutes under three conditions: No Exoskeleton (NO_EXO), Exoskeleton Active (EXO_ON), and Exoskeleton Passive (EXO_OFF).
- Measured outcomes included Physiological Cost Index (PCI), Peak Heart Rate (HR_Peak), and Rating of Perceived Exertion (Borg RPE).
Main Results
- Active exoskeleton assistance (EXO_ON) significantly reduced PCI compared to both NO_EXO and EXO_OFF conditions.
- RPE was also significantly lower with active assistance than with unassisted or passive conditions.
- Peak Heart Rate was lowest in the EXO_ON condition, but differences were not statistically significant.
- The exoskeleton effectively offset the physiological burden of its own mass, resulting in a net reduction in cardiovascular effort.
Conclusions
- Soft hip exoskeletons can improve walking efficiency and reduce perceived exertion during uphill walking in older adults.
- These devices may help mitigate fatigue-related risks and support safer physical activity in aging populations.
- Further research may explore long-term benefits and broader applications in real-world settings.
Frequently Asked Questions
Executive Industry Relevance
Quantitative assessment of assistive exoskeletons in older adults provides actionable data for device validation and risk mitigation in mobility-focused R&D. Measuring physiological cost and perceived exertion enables objective evaluation of intervention impact at the discovery and prototype stage. These insights inform translational strategies for wearable technologies targeting age-related mobility decline.
Strategic Applications in Biopharma R&D
Early Discovery & Target Validation
- Enables hypothesis testing on device efficacy in reducing physiological burden during exertion.
- Supports functional validation of assistive technologies for neuromuscular fatigue mitigation.
- Provides quantitative endpoints for mechanistic de-risking of wearable interventions.
Screening & Assay Development
- Establishes standardized treadmill-based protocols for reproducible physiological measurements.
- Generates validated quantitative outputs (PCI, RPE, HR_Peak) for device comparison.
- Facilitates screening of assistive device prototypes for efficacy and user impact.
Translational & Preclinical Research
- Aligns device performance metrics with real-world functional outcomes relevant to aging populations.
- Supports continuity from controlled laboratory validation to preclinical assessment of mobility interventions.
- Informs risk-adjusted advancement of wearable technologies for age-related functional decline.
Pipeline & Workflow Integration
This protocol positions physiological and perceptual measurement as a critical step from early device discovery through preclinical validation in mobility research.
- Discovery Biology: Quantifies intervention impact on neuromuscular fatigue and exertion.
- Screening: Provides reproducible, quantitative endpoints for device comparison and optimization.
- Analytics: Delivers statistical outputs (PCI, RPE, HR_Peak) to support cross-condition analysis.
- Translational Research: Bridges laboratory findings to functional outcomes in target populations.
- Enterprise Reuse: Establishes a reusable framework for evaluating assistive mobility devices.
Operational & Enterprise Impact
- Scientific Value: Increases predictive confidence in device efficacy and safety for older adults.
- Operational Value: Standardizes measurement of physiological and perceptual endpoints across studies.
- Strategic Value: Informs go/no-go decisions for device advancement based on quantitative risk reduction.
- Portfolio Impact: Enables risk-adjusted prioritization of wearable mobility interventions.
Implementation Considerations
- Requires expertise in exercise physiology, biomechanics, and gerontology for protocol execution.
- Needs access to instrumented treadmills and validated physiological monitoring equipment.
- Demands cross-team standardization of measurement protocols and data analysis.
- Must consider adaptation of protocols for different age groups or mobility impairments.
- Limited to controlled laboratory settings; real-world generalizability requires further validation.
