Delt Raises: How Different Hand Grips and ROM Used Can Effect Muscle Activation
A comparative experimental study.
This study investigated how variations in handgrip and range of motion (ROM) affect muscle activity in the deltoid muscles during specific exercises. The research was conducted with 14 resistance-trained male participants to provide insights to enhance strength training programs for athletes and fitness enthusiasts.
Given the complexity of shoulder mechanics and the importance of targeting specific deltoid heads for muscle-building, understanding these variations is crucial for optimising training efficacy.
Key Points
Participants: 14 resistance-trained men (average age 23.6 years) were selected based on their training history and absence of upper extremity injuries.
Exercises Analysed:
Dumbbell Front Raise (DFR)
Dumbbell Lateral Raise (DLR)
Dumbbell Rear Delt Raise (DRDR)
Methodology:
Participants performed exercises using three different handgrips (pronate, supinate, hammer/neutral) and two ROM variations.
Electromyography (EMG) was used to measure muscle activity in the anterior, medial, and posterior deltoid heads.
Findings:
For DFR, the anterior deltoid showed the highest EMG activity with a pronate grip (51.57%), significantly higher than with a hammer grip (43.36%).
In DLR, medial deltoid activity peaked at limited ROM (20.74%), with anterior head activity also higher at limited ROM compared to full ROM.
For DRDR, the medial deltoid again had the highest activity with a neutral grip (24.47%), while posterior deltoid activity was greater in eccentric phases with a standard grip compared to a hammer grip.
