balance perturbations. Thirty-six volunteers, divided into four groups [young (YA), middle-
age (MA40 and MA50), and old (OA) adults], stood on a platform that was either kept
stationary, moved backward, or moved forward. EMG onset, EMG time-to-peak, iEMG, and
agonist–antagonist co-activation, as well as cumulative angular excursion, maximum center
of mass (CM) backward displacement, and CM time-to-reversal were assessed after forward …