Comparison among the EMG Activity of the Anterior Deltoid and Medial Deltoid During Two Variations of Dumbbell Shoulder Press Exercise

To analyze the muscle activation of anterior and medial deltoid muscles while performing two different grip variations of dumbbell shoulder press.

Ten healthy male participants (age = 20.9 ± 1.449 years, height = 1.71 ±.038 m, weight =69.65 ± 2.92 kg) from Lakshmi Bai National Institute of Physical Education (Gwalior, M.P, India) were recruited as a sample of the study. The participants performed 5 repetitions of two different grip variations of dumbbell shoulder press. The exercises were Arnold Dumbbell Press (ADP) and Overhead Dumbbell Press (ODP). Surface Electromyography (SEMG) was used to record the muscle activation and for measuring muscle electrical activity that occurs during muscle contraction.

Paired t-test was used to detect mean differences between the two variations of dumbbell shoulder press. It was found that Anterior and Medial Deltoid muscles were more active while performing ADP (AD-1346.4292.495; MD-827.5 146.426) as compared to ODP (AD-1043.4 141.299; MD-725.4 100.4). Also while performing both the exercises, the muscle activation of anterior deltoid was found to be much higher than Medial Deltoid.

Arnold dumbbell press was more effective exercise for the activation of Anterior and Medial deltoid muscles as compared to the Overhead Dumbbell Press. Anterior deltoid acts as primary muscle while performing both the exercises, as the muscle activation is much higher as compared to medial deltoid.