The Effects of Changes in Hand Position on the Electromyographic Activities of the Shoulder Stabilizer Muscles during Push-up Plus Exercises on Unstable Surfaces

Abstract

Abstract.[Purpose] The purpose of the present study was to examine the effects of changes in hand position on the electromyographic activities of the shoulder stabilizer muscles during push-up plus exercises (PUPE) on unstable surfaces.[Subjects] The subjects of the present study were normal adults in their 20s (n=15). PUPEs were performed with the hands in the neutral positions (NP), internal rotation positions (IRP), and external rotation positions (ERP) using a sling device for the unstable surface. [Methods] We measured the electromyographic activities of the wrist flexor (WF), the wrist extensor (WE), the biceps brachii (BB), the triceps brachii (TB), the upper trapezius (UT), the lower trapezius (LT), the serratus anterior (SA), and the pectoralis major (PM). The muscle activites were compared and analyzed using electromyography.[Results] When hand position changed, WF activity in NP, and SA activity in ERP, were significantly different from their respective activities in the other positions. [Conclusion] To selectively enhance the electromyographic activity of the SA during PUPE using a sling device as an unstable surface, we consider performance of PUPE in ERP is an effective intervention.

EMG activity of the serratus anterior and trapezius muscles during the different phases of the push-up plus exercise on different support surfaces and different hand positions

“…The hand position in Pup changes the degree of arm elevation in the frontal plane, altering the range of arm movement as well as the movement itsself 10 , 11 , 12 ) . Flexion, abduction or horizontal abduction is required at the shoulder joint, leading respectively, to upward rotation with retraction, or adduction of the scapula.…”

“…Different studies have examined the effect of single factors, such as the support surface 7 , 9 ) or the hand orientation on muscular activity during the PuP 10 , 11 , 12 , 13 ) . Due to the complexity of the exercise performance, it is a closed-kinetic activity of the whole body, the effect of different parameters acting simultaneously on the muscle activity must be investigated.…”

The Effects of Scapular Stabilization Exercises Accompanied by Spine Stabilization Exercises Using An Unstable Surface on Muscle Activities for Subjects with Scapular Winging

“…To further increase muscle activity during exercise, clinicians commonly instruct patients to perform the exercises on an unstable base of support. Many studies have shown that the instability created by an unstable surface increases the demands on the neuromuscular system, thereby increasing muscle activity and improving the stability of the proximal joints and trunk [19,20]. Biscarini et al [21] found that compared with training on a stable surface, performing spinal stabilization exercises on an unstable surface produced more anterolateral abdominal muscle activity and increased muscle activation in the shoulder.…”

Effect of the Push-up Plus (PUP) Exercise at Different Shoulder Rotation Angles on Shoulder Muscle Activities

“…PUP is an effective exercise method that decreases action of the trapezius muscle and increases activity of SA. Among PUP exercises, it is known that exercise on an unstable base of support has the most effect 4 , 5 ) . Exercise methods for shoulder stabilization, to improve rehabilitation of patients with shoulder damage, have continuously improved with time.…”