Abstract
Increased metabolic cost of walking after stroke limits mobility and quality of life for millions of individuals. Existing portable assistive devices, primarily targeting the ankle joint, have failed to alleviate this burden. Here, we tested a portable, lightweight hip exoskeleton providing bilateral assistance during walking for individuals with chronic post-stroke hemiparesis. The exoskeleton significantly reduced the net metabolic cost of walking by 18 ± 2% (mean ± standard error, p = 0.0002) in seven participants during treadmill walking—a reduction sufficient to potentially lessen fatigue and extend walking duration— compared to walking without the device. This improvement was associated with a 29 ± 6% reduction in positive biological hip work (p = 0.0052), indicating effective offloading of the hip joints. These results provide the first evidence that portable hip exoskeleton assistance can improve walking economy in stroke survivors, offering a promising therapeutic strategy to enhance real-world mobility and functional recovery in this large clinical population.
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All data supporting the findings of this study are available within the article and its supplementary files. Any additional requests for information can be directed to, and will be fulfilled by, the corresponding author. Source data are provided with this paper. All data generated in this study have been deposited in a figshare repository [https://doi.org/10.6084/m9.figshare.30158260]. Source data are provided with this paper.
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Acknowledgements
We wish to acknowledge the contribution of all study participants. We thank S. Edgely for helping with participant recruitment. This study was funded in part by National Institute for Occupational Safety and Health under grant number T42OH008414 (T.L., K.P.), in part by the National Science Foundation under grant number 2046287 (T.L.), in part by National Science Foundation Graduate Research Fellowship Program under grant number 2139322 (K.P.), and in part by the National Institutes of Health under project 1T32TR004394-0 (R.M.).
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T.L. supervised all aspects of the project. K.P., R.M., L.G., and T.L. developed the exoskeleton and controller. K.P., R.M., and T.L. conducted human experiments. K.P., R.M., L.G., B.F., and T.L. analyzed the data. All authors contributed to manuscript preparation.
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Pruyn, K., Murray, R., Gabert, L. et al. Portable hip exoskeleton improves walking economy for stroke survivors. Nat Commun (2026). https://doi.org/10.1038/s41467-026-69580-0
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DOI: https://doi.org/10.1038/s41467-026-69580-0
