Abstract
The purpose of this study was to investigate associations among gait, standing
balance and muscle contraction latency, sustained contraction during weight bearing on the
lower limbs while sitting, in stroke patients. Thirty-five stroke patients, classified by gait
independence, were assessed for lower limb loading force using a surface electromyogram
（EMG） on vastus medialis and biceps femoris longus muscles in the paretic side. They
performed 5-second maximal voluntary contraction and 10-second sustained contraction
under lower limb loading while sitting, and the root mean square （RMS） of EMG was
determined. Repeated measures two way of analysis of variance were used to analyse the
effect of gait independence and time factors. Patients that could gait independently showed a
significant higher RMS of paretic vastus medialis muscle than those that could not. There
were significant correlations among maximal voluntary contraction and dynamic balance of
functional balance scale. These findings suggest that maximal muscle power and sustained
contraction by paretic lower limb are factors that correlate with gait and standing balance.
