Yoga Glossary · Muscles
Deltoids
The cap muscles of the shoulders — they lift the arms in every direction.
The deltoid is the rounded muscle that caps each shoulder joint. It has three heads: the anterior (front) head helps lift the arm forward, the middle head lifts it out to the side, and the posterior (rear) head draws it backward. All three work together whenever the arm moves against gravity or body weight.
In yoga the deltoids are quiet heroes. They hold the arms overhead in Chair and Warrior I, reach the arms wide in Warrior II and Triangle, and share the load with the chest and triceps whenever you press the floor away in Plank, Chaturanga and Down Dog. Weak or tired deltoids are a common reason shoulders creep toward the ears in arm-supported poses.
In practice
- Feel them wrap the top of the shoulder whenever the arms lift or bear weight.
- First to fatigue in long Plank and Down Dog holds — shaking arms usually means deltoids asking for a rest.
- Pair them with the rotator cuff: deltoids move the arm, the cuff keeps the joint centered while they do it.
Poses that engage it
- Arms Overhead (Upward Salute)
- Chair Pose
- Warrior I
- Warrior II
- Reverse Warrior
- Extended Side Angle
- Crescent Lunge
- Eagle Pose
- Locust Pose
- Bow Pose
- Camel Pose
- Wheel Pose
- Chaturanga
- Side Plank
- Downward Facing Dog
Poses that lengthen it
Related terms
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The Yoga Glossary is an educational study reference. Definitions are standard yoga and anatomy knowledge in plain language; nothing here is medical advice.