Effects of Tai Chi on a Functional Arm Reaching Task in Older Adults: A Cross-Sectional Study

This study quantified the effect of aging and the long-term practice of Tai Chi on upper limb movement control, indicated by performance outcome (temporal) and performance production (amplitude) measures, on a multiplanar stand-reaching (i.e., functional) task. Twelve Tai Chi practitioners (TCPs), 11 age-matched older nonpractitioners (ONPs), and 12 young subjects performed cued, flexion-reaching, and abduction-reaching tasks using a custom set-up. Surface EMG and acceleration data sampled from wireless sensors rendered performance outcome (reaction time, burst duration, time to peak, and movement time) and performance production (normalized EMG amplitude and peak acceleration) measures. Young subjects and TCPs demonstrated better performance outcome and performance production than ONPs. Relative-effect computations (i.e., the effect of Tai Chi expressed as a percentage of the effect of aging) showed that TCPs exhibited approximately 20-60% (flexion) and 20-100% (abduction) improvement in reaching task performance compared with ONPs. Tai Chi practitioners displayed better arm movement control than ONPs on a relatively challenging and functional stand-reaching task.