Learning From Falling: Perturbation-based Training to Prevent Falls in Older Adults

Study Summary

The investigators will evaluate the difference between a commonly accepted paradigm of balance training (BT) and a more dynamic and task specific form of balance training, perturbation-based training (PBT) in older adults. BT is a key evidenced based strategy for preventing falls in older adults, however it needs to be regular (2hours/week) and long term (\>6moths) while the average effect is only moderate (24%). The reason for the moderate effect on falls is like to be the non-specific stimulus presented during BT. That is, training tends to be quasi-static and slow and largely based on movements described as strength training. However, when an individual loses balance, they are most often required to implement a rapid and dynamic response. Furthermore, while older adults who are unable to recover balance well have generally lower strength, our recent work has demonstrated that it is not their force producing capability that limits them. Rather it is the ability to access moderate levels of muscular force very rapidly and early in the recovery step that differentiates successful versus unsuccessful recovery of balance. Importantly, the ability to produce an effective and rapid recovery step is predicative of avoiding future real world falls. An emerging fall prevention training regimen is perturbation-based training (PBT). PBT involves rapidly disrupting balance requiring the participant to take rapid steps to recover balance. This is commonly achieved on a laboratory treadmill equipped with a safety harness to prevent actual falls during training. By simulating "real-world" balance challenges such as slips and trips, PBT provides a direct means for learning how to recover balance and avoid falls. It has been demonstrated that with only a few PBT sessions, older adults make rapid and dramatic improvements in balance recovery performance, retain the skills long-term and potentially suffer fewer falls over extended periods. This study builds on the previous publishe

Primary Outcome

Margin of stability describes dynamic stability of an individual during stepping. It quantifies the location of the velocity adjusted center of mass compared to the base of support. Positive numbers reflect stability while negative numbers reflect instability. Margin of stability during balance recovery is related to future fall.

Interventions

• BEHAVIORAL Balance recovery
• BEHAVIORAL Postural Sway