Design considerations for technology-assisted fall-resisting skills training trials in older adults: A pilot and feasibility study.

Weight-shifting tasks were perceived as balance training by most participants, indicating their potential as placebo tasks in a future RCT.

• Eleven healthy older adults participated in the pilot study.
• Placebo tasks included static weight-shifting exercises and dual-task walking.
• Most participants perceived weight-shifting tasks as balance training, supporting their use as a credible placebo control.
• The dual-task walking condition was also tested as a potential placebo task.

Obstacle avoidance difficulty increased most with fast approach speed and large obstacle sizes.

• Participants walked on a treadmill and avoided projected obstacles varying in size, approach speed, and available response time.
• Fast approach speed and large obstacle sizes were identified as the most influential parameters for increasing task difficulty.
• These findings inform the calibration of obstacle difficulty settings for a future RCT of proactive gait adaptability training.
• Available response time was also manipulated as a difficulty parameter.

A margin of stability-based threshold did not consistently align with perceived balance loss or observer judgement as an evaluation method for gait robustness.

• Gait robustness was assessed using perturbations of increasing magnitude.
• The margin of stability (MoS) following each perturbation was compared with participants' perceived balance loss and researchers' observations.
• The MoS-based threshold showed inconsistent alignment with both subjective perceived balance loss and objective observer judgement.
• This finding suggests that MoS alone may not be a sufficient threshold measure for evaluating gait robustness in this context.

Anxiety did not increase with more unpredictable perturbation tasks when perturbations were introduced gradually.

• Perturbations with increasing unpredictability were applied during reactive gait recovery tasks.
• Participants reported their anxiety scores after each condition.
• When perturbations were introduced gradually, anxiety scores did not increase as unpredictability increased.
• This finding suggests that gradual introduction of unpredictable perturbations is a feasible and acceptable approach for older adults in a training context.

Fall-resisting skill tasks including proactive gait adaptability, gait robustness, and reactive gait recovery were generally feasible for healthy older adults.

• Eleven healthy older adults completed assessment and training tasks for each of the three fall-resisting skills.
• All tasks were performed on a treadmill under various experimental conditions.
• General feasibility was confirmed across all three fall-resisting skill domains.
• The study was designed as a pilot to inform the design of a subsequent randomized controlled trial.