Learning From Laboratory-Induced Falling: Long-Term Motor Retention Among Older Adults

Background. Falls in older adults are a major health and public problem. It is thus imperative to develop highly effective training paradigms to reduce the likelihood of falls. Perturbation-training is one such emerging paradigm known to induce shorter-term falls reduction in healthy young as well as older adults. Its longer-term benefits are not fully understood, however. The purpose of this study was to determine whether and to what degree older adults could retain their fall-resisting skills acquired from a single perturbation training session. Methods. Seventy-three community-dwelling older adults (≥ 65 years) received identical single-session perturbation training consisting of 24 slips. This was delivered through unannounced unlocking (and mixed with relocking) of low-friction, moveable sections of the walkway, and a single retest scheduled based on a 3-stage sequential, pre-post-retest design. Outcome measurements, taken upon the first (novel) and the24th (final) slip of the initial session and the retest slip, included fall-or-no-fall, and stability (quantified by the shortest distance form relative motion state of the center-of-mass and the base-of-support to the limits of stability) at instants prior to (proactive) and after (reactive) the onset of the slip. Results. The training boosted subjects’ resilience against laboratory-induced falls demonstrated by a significant reduction from 42.5% falls on the first slip to 0% on the 24th slip. Rate of falls occurred during the laboratory retest remained low in 6-month (0%), 9-month (8.7%) and 12-month retest (11.5%); with no significant difference between the three time intervals. Such reduction of laboratory-induced falls and its retention were attributable to the significant training-induced improvement in the proactive and reactive control of stability. Conclusion. This unique pre-post-retest design enabled us to provide scientific basis for the feasibility of a single session of perturbation training to “inoculate” older adults and to reduce their annual risk of falls in everyday living.