The objective of this study is to analyse the electromyography activity of the biceps femoris muscle during various exercises performed with maximal isometric contractions at the same muscle length.
The study was conducted on 15 right hand healthy subjects. with age between 20 and 30 years. In prone position the participants were posed with their feet out of the clinical bed and a hard pillow below their stomach; in supine position their feet were posed on a wooden cube in order to
reproduce the same angle of hip flexion held in the prone position. In these positions the study analysed the maximal isometric movements involving the biceps femoris in the role of agonist muscle or pelvis stabilizer.
In the supine position the subjects performed the right hip extension and the left hip flexion. In the prone position the hip extension and the right knee flexion.
The subjects were asked to perform three repetitions for each one of the four exercises. following a randomised sequence. Each movement has been kept for 5 seconds. The pause between two consecutive movements lasted 2 minutes.
During each single exercise. the study registered the surface electromyography activity of the biceps femoris long end and the pelvis’ kinematics through a 6 cameras system (ELITE. BTS). The EMG activation intensity of the biceps femoris for each subject. was reported computing the mean value of the 3 trials performed for each exercise.
For comparing the 4 exercises the study utilised the ANOVA for repeated measurements. both for the electromyography activation intensity and for pelvis mobility during the exercises.
The eventual correlation between the electromyography activity with the pelvis mobility and the exercise sequence was analysed with the Pearson’s Test.