Short-Term Versus Long-Term Perturbation-Based Balance Training Program on Balance Function-A Secondary Analysis of Two Randomized Controlled Trials.

INTRODUCTION: Perturbation-based balance training (PBT), which involves repeated exposure to unannounced balance challenges, has been shown to reduce fall risk in older adults. However, the optimal duration of PBT interventions to achieve generalized improvements in balance remains unclear. AIMS: This study aimed to compare the effects of 1-month versus 3-month PBT programs on reactive stepping, voluntary stepping, and postural control in older adults. METHODS: We conducted a secondary analysis of two randomized controlled trials including 40 community-dwelling older adults (aged ≥ 70), divided equally into 1- and 3-month PBT groups. Both groups received multidirectional treadmill-based perturbation training. Pre- and postintervention assessments included reactive stepping responses, voluntary stepping under single- and dual-task conditions, and quiet stance postural sway measures. Two-way repeated-measures analyses of variance and effect sizes were used to evaluate group-by-time interactions. RESULTS: Both training intervention durations significantly improved participants' ability to withstand higher perturbation magnitudes (∼65%-70%) without improvements in reactive step kinematics. However, only the 3-month group demonstrated significant improvements in voluntary stepping speed in standing and postural sway measures. DISCUSSION AND CONCLUSION: While a 1-month PBT was sufficient to enhance reactive fall resistance, only the 3-month program led to broader transfer effects to voluntary balance and "static postural control." A 1-month PBT intervention can effectively enhance reactive balance control, but longer training durations may be necessary to achieve generalized improvements in balance control and voluntary step movements relevant to fall prevention in older adults.