AUTHOR=Song Patrick Y. H. , Sturnieks Daina L. , Davis Michael K. , Lord Stephen R. , Okubo Yoshiro 

TITLE=Perturbation-Based Balance Training Using Repeated Trips on a Walkway vs. Belt Accelerations on a Treadmill: A Cross-Over Randomised Controlled Trial in Community-Dwelling Older Adults

JOURNAL=Frontiers in Sports and Active Living

VOLUME=Volume 3 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/sports-and-active-living/articles/10.3389/fspor.2021.702320

DOI=10.3389/fspor.2021.702320

ISSN=2624-9367

ABSTRACT=Background: Walkway and treadmill induced trips have contrasting advantages: walkway trips have high ecological validity whereas simulated-trips on a treadmill have high clinical feasibility for perturbation-based balance training (PBT). This study aimed to (i) compare adaptations to repeated overground trips with repeated treadmill trips in older adults, and (ii) determine if adaptations to repeated treadmill-simulated trips can transfer to an actual trip on the walkway.
Method: Thirty-eight healthy community-dwelling older adults underwent one session each of walkway and treadmill PBT in a randomised crossover design on a single day. For both conditions, 11 trips were induced to either leg in pseudorandom locations interspersed with 20 normal walking trials. Dynamic balance (e.g. margin of stability) and gait (e.g. step length) parameters from 3D motion capture were used to examine adaptations in the walkway and treadmill PBT and transfer of adaptation from treadmill PBT to a walkway trip. 
Results: No changes were observed in normal (no-trip) gait parameters in both training conditions, except for a small (0.9 cm) increase in minimum toe elevation during walkway walks (P < 0.01). An increase in margin of stability and recovery step length were observed during repeated walkway trips only (P < 0.05). During repeated treadmill trips, a decrease in recovery trunk sway range was observed (P < 0.05). These adaptations to treadmill PBT did not transfer to a walkway trip.
Conclusions: This study demonstrated that older adults could learn to improve dynamic stability by repeated exposure to walkway trips. Exposure to simulated trips on a treadmill improved trunk control in older adults but this adaptation did not transfer to an actual trip. To enhance the utility of treadmill PBT for overground trip recovery performance, further development of treadmill PBT protocols is recommended to improve ecological authenticity.