Electromyography of stair locomotion in elderly men and women

The electromyographic activity of five lower limb muscles during stair locomotion was examined in ten men and women aged 76-83 years. Phasic activity patterns were compared with those in previous studies of young adults to determine differences indicative of an enhanced need to provide joint stability. The temporal patterning of the stair gait cycle showed no evidence of an increase in weight bearing time to aid balance control. There was a high level of consistency between phasic activity patterns in the present and previous studies in all muscles with the exception of biceps femoris. Factors contributing to its increased level of activity in our elderly subjects are discussed. There was evidence of modifications to muscular activity to provide additional joint stability at both the knee and ankle. This was most apparent in stair descent during the transition to, and the early weight acceptance period.