Muscles
Origin, insertion, action and the best exercises for each muscle, shown in 3D.
Shoulders
- Anterior deltoid · Front deltFlexes and medially rotates the arm at the shoulder
- Lateral deltoid · Side deltAbducts the arm (raises it out to the side)
- Posterior deltoid · Rear deltExtends, horizontally abducts and laterally rotates the arm
- Supraspinatus · Rotator cuff muscleAssists the deltoid in abducting the arm and holds the humeral head in the socket
- Infraspinatus · Rotator cuff muscleLaterally rotates the arm and stabilises the shoulder joint
- Teres minor · Rotator cuff muscleLaterally rotates the arm and stabilises the shoulder joint
- Subscapularis · Rotator cuff muscleMedially rotates the arm and stabilises the shoulder joint
Chest
Back
- Upper trapezius · TrapsElevates and upwardly rotates the scapula
- Middle trapeziusRetracts the scapula (pulls the shoulder blades together)
- Lower trapeziusDepresses and upwardly rotates the scapula
- Latissimus dorsi · LatsExtends, adducts and medially rotates the arm
- RhomboidsRetract, elevate and downwardly rotate the scapula
- Teres majorExtends, adducts and medially rotates the arm
- Erector spinae · Spinal erectorsExtends and laterally flexes the spine
Arms
- Biceps brachii · BicepsFlexes the elbow and supinates the forearm
- BrachialisFlexes the elbow in any forearm position
- BrachioradialisFlexes the elbow, especially with a neutral grip
- Triceps brachii · TricepsExtends the elbow; the long head also extends the arm
- Forearm flexorsFlex the wrist and fingers and provide grip strength; the pronator teres pronates the forearm
- Forearm extensorsExtend the wrist and fingers
Core
- Rectus abdominis · Abs, six-packFlexes the trunk and braces the abdomen
- External obliqueRotates the trunk to the opposite side and bends it to the same side; compresses the abdomen
- Internal obliqueRotates and laterally flexes the trunk; compresses the abdomen
- Transversus abdominis · TVACompresses the abdomen and stabilises the lumbar spine
Hips & glutes
- Gluteus maximus · GlutesExtends and laterally rotates the hip
- Gluteus mediusAbducts the hip, its front fibres rotate it inward, and it keeps the pelvis level
- Gluteus minimusAbducts and medially rotates the hip
- Tensor fasciae latae · TFLAbducts, flexes and medially rotates the hip
- Iliopsoas · Hip flexorsFlexes the hip and the trunk
- Deep hip rotatorsLaterally rotate and stabilise the hip