“…The mean speed of COP displacements (mm/s) is the sum of the displacements scalars, i.e., the cumulated distance, over the sampling period (Maki et al, 1994). The COP speed parameter represents the amount of activity required to maintain stability (Geurts et al, 1993) and was demonstrated to be very sensitive when using the tendon vibration technique (Uimonen et al, 1996).…”