2.2.2. Reaction time
All participants completed a simple reaction time (SRT) task where
upper limb (index finger) and lower limb (foot) responses were
collected. After completing 5 practice trials, each person completed 25
trials with each segment (the initial 10 trials were used within the
PPA design for derivation of falls risk). Participants responded to a
visual cue (light) by depressing a timing switch. For the foot SRT,
participants placed the distal end of their foot over a pedal switch
placed on the floor. When the light stimulus came on, subjects pressed
down on the switch with their foot/toe (with a plantar flexion
movement) as quickly as possible.