Emerging evidence indicates exercise training improves mobility and cognition and reduces falls in older adults, but underlying mechanisms are not well understood. This study tested the hypothesis that change in dual-task walking capacity mediates the positive effect of Tai Ji Quan and multimodal exercise on physical performance, activity confidence, global cognition, and falls among community-dwelling older adults at high risk of falling.
We conducted a secondary analysis of a 6-month randomized clinical trial comparing Tai Ji Quan: Moving for Better Balance (TJQMBB) and multimodal exercise to stretching exercise in a sample of 670 older adults aged ≥70 years who had a history of falls or impaired mobility. Distal outcome measures, ascertained at a 12-month follow-up, were the Short Physical Performance Battery (SPPB), Activities-Specific Balance Confidence (ABC), Montreal Cognitive Assessment (MoCA), and falls. The mediator hypothesized to account for the intervention effects was dual-task cost estimated by calculating changes in gait speed from single-task to dual-task walking from baseline to the end of intervention.
At 12 months, compared with stretching exercise, multimodal exercise significantly improved SPPB and ABC outcomes and reduced the number of falls (P < 0.05). However, it did not lower dual-task cost or mediate the intervention effects on distal outcomes. In contrast, TJQMBB significantly reduced dual-task cost relative to multimodal and stretching exercises (P < 0.05) which in turn resulted in improvements in lower-extremity physical performance, activity confidence, global cognitive function, and reductions in falls (P < 0.05) during follow-up.
Enhanced dual-task walking capacity as a result of Tai Ji Quan training mediated improvements in physical and cognitive outcomes in older adults at high risk of falling.
1Oregon Research Institute, Eugene, OR
2Department of Exercise and Health Science, Willamette University, Salem, OR
3Department of Human Physiology, University of Oregon, Eugene, OR
Correspondence: Fuzhong Li, Ph.D. Oregon Research Institute, 1776 Millrace Dr. Eugene, OR 97403, Phone: 541-484-2123, E-mail: firstname.lastname@example.org
Competing interests: Li reports a grant from National Institutes of Health during the conduct of the study and being the founder and owner of Exercise Alternatives, LLC, a consulting company to which a voluntary licensing fee for Tai Ji Quan: Moving for Better Balance is paid. No other disclosures were reported.
Contributorship: All authors contributed the planning, drafting and approval of this manuscript
Acknowledgements: This work was supported by grant AG045094 from the National Institute on Aging. The results of the study are presented clearly, honestly, and without fabrication, falsification, or inappropriate data manipulation. The results of the present study do not constitute endorsement by ACSM.
Approved for Publication: 17 May 2019