Electromyographic activity of the hindlimb muscles during the walk, trot and canter

Abstract

SummaryThe tensor fasciae latae and the middle part of the biceps femoris were investigated electromyographically and kinematically in 4 Thoroughbred horses with or without a rider during the walk, trot and canter. EMG activity of the tensor fasciae latae began in the middle of the stance phase and ceased in the early period of the swing phase during the walk and trot in horses with or without a rider. During the canter, the onset and termination of muscle activity began earlier than during symmetrical locomotion. Its EMG activity had a higher amplitude during the stance phase than during the swing phase. These results indicate that the tensor fasciae latae may act as an extensor or stabiliser of the stifle joint during locomotion. During the walk, EMG activity of the middle part of the biceps femoris was silent or weak. During the trot and canter, the muscle had a high amplitude of EMG activity and was active from the middle of the swing phase to the early or middle period of the stance phase in horses with or without a rider. This part of the muscle may work as an extensor of the hip joint during locomotion.