Learning to Resist Gait-Slip Falls: Long-Term Retention in Community-Dwelling Older Adults

Abstract

Objectives To determine whether the fall-resisting skills acquired from a single perturbation training session can be retained for 6-months or enhanced by an intermediate ancillary session. Design A randomized controlled trial. Setting Biomechanics research laboratory. Participants Forty-eight community-dwelling elderly (>65 years). Intervention Initial perturbation training applied to all subjects using low-friction platforms to induce, unannounced blocks of repeated right-side slips, interspersed with non-slips. The single-session group retested with only one slip 6-months later. The dual-session group received an additional slip at 3-month, post initial session, followed by a retest slips at 6-months. Main Outcome Measures Slip outcome (incidence of falls and balance loss), dynamic stability (based on the center-of-mass position and velocity) and vertical limb support (based on hip height). Results Subjects in both groups significantly reduced fall and balance loss incidence from first to last training slips, which resulted from improved stability and limb support control. Both groups demonstrated significant retention in all outcome measures at 6-months compared to the first novel slip; although performance decay was evident in comparison to the last training slip. The ancillary slip at 3-months led to significantly better control of stability, and hence reduced balance loss outcome in the dual-session group at 6-months, than the single-session group. Conclusions Motor memory could be retained for 6-months or longer following a single-session of fall-resistance training, although a single “booster” slip could further impede its decay. Through the experience of slipping and falling, it may be possible to “inoculate” older adults against potentially life threatening falls.

Perturbation‐based balance training for falls reduction among older adults: Current evidence and implications for clinical practice

“…also investigated the effect of experiencing a single slip perturbation 3 months after a perturbation session on retention at 6 months 45. Their results show that such a “booster” session helped participants to retain improvements in reactive balance control 45. These findings are potentially important for clinical practice, as they show that after an initial training period, long‐term retention of the benefits of PBT is possible and can be enhanced with short additional sessions.…”

“…Previous studies reported that both healthy older adults and patients with Parkinson's disease, after experiencing a single session of perturbations, showed at least partial retention of reactive balance control improvements over short periods of 24 h 27, 38. Studies with healthy older adults have also shown retention over longer periods of 6,45, 46 9 and 12 months46 in laboratory settings. Retention in compensatory step length has also been shown in patients with Parkinson's up to 2 months after a 2‐week long PBT intervention 47.…”

“…Bhatt et al . also investigated the effect of experiencing a single slip perturbation 3 months after a perturbation session on retention at 6 months 45. Their results show that such a “booster” session helped participants to retain improvements in reactive balance control 45.…”

“…In the aforementioned studies, a variety of magnitudes were used, that were either fixed or progressive with training. High‐magnitude perturbations, where participants initially require support from the harness to regain stability, appear to trigger fast and significant adaptation in recovery behavior, and long‐term retention of motor adaptations 31, 45, 46, 48. However, studies based in clinical settings have generally used a more progressive increase in perturbation magnitude, starting with lower‐magnitude perturbations and progressing based on the supervising physiotherapist's judgement 34, 37.…”

“…As aforementioned, this might depend on the magnitude of perturbations used. With high‐magnitude perturbations, relatively low PBT volume might be required for long‐term benefits 31, 45, 46, 48. With lower‐magnitude perturbations, which might be more feasible with frail, older adults or different patient groups, longer training periods might be required in order to result in a significant reduction in falls incidence.…”