In previous studies of rapid elbow movements in young healthy men, characte
ristic task-dependent changes in the patterns of muscle activation when mov
ement speed or distance was varied have been reported. In the present study
, the authors investigated whether age or gender is associated with changes
in the patterns of muscle activity previously reported in young men. Arm m
ovements of 10 healthy older and 10 healthy younger participants (5 men and
5 women in each group) were studied. Surface electromyograms (EMGs) from a
gonist (biceps) and antagonist (triceps) muscles, kinematic and kinetic par
ameters, as well as anthropometric and strength measures were recorded. All
4 groups of participants showed similar task- (distance or speed) dependen
t changes in biphasic EMG activity. Similar modulation of the initial rate
of rise of the EMG, integrated agonist and antagonist EMG activity, as well
as their relative timing were observed in all 4 groups. Those results sugg
est that older individuals of both genders retain the control strategies fo
r elbow movements used by young individuals. Despite the qualitative simila
rities in the patterns of muscle activation, the men moved more quickly tha
n the women, and younger participants moved more quickly than older partici
pants. Those performance differences could not be explained in terms of dif
ferences in body size and strength alone.