Selected Muscles Electromyography Activity in Kyphosis Corrective Exercises with and without Head Retraction

One of the most common postural abnormalities is hyperkyphosis chest with its increase associated with an increase in forward head. Therefore, the aim of the present study was to investigate selected muscles electromyography activity in kyphosis corrective exercises with and without head retraction.
In the current study, a sample of 15 non-athletic male students (18-25 years) with hyper-kyphosis higher than 42 degrees were selected. The activity of electromyographic with surface electrodes of Sternocleidomastoid muscles, upper trapezius, middle trapezius, and rhomboid in Cobra, W, and Y motions with and without head retraction were recorded using wireless EMG (16 channels, Bayamed Company). For intra-group comparison of muscle activity in the two states, t-test was performed with a significance level of 95% (α=0.05).
The results showed that the activity of upper trapezius muscle and mid trapezius (p <0.05) in y motion with and without head retruction was statistically significant, but no significant difference was found in the activities of the other two muscles. Also, in the movement of W with and without retruction, the levels of activity of all four muscles were statistically significant (p <0.05). In Cobra movement, there was a significant difference in the levels of activity of upper trapezius muscles and Sternocleidomastoid between the two states with and without retruction of the head, but no significant difference was found in the activities of the other two muscles.
According to the results, a decrease in the upper trapezius activity and an increase in the mid trapezoid activity in y motion with head retraction were observed. It was also shown that in the movement of W with head retraction, except for the Romboid muscle, the activities of the other three muscles increased. In cobra movement, the activities of upper trapezius muscle and Sternocleido-astoid in head retraction were more than those without head retraction. The results also indicate that the position of the head has a different effect on the muscles electromyography in kyphosis corrective exercises. Therefore, it is recommended that application of these moves to treat kyphosis be performed with caution. All in all, more information is necessary to complete our knowledge in this regard.