Dumbbell Cross Body Extension

A cross body triceps extension is a resistance exercise, which involves the primary elbow extensor, the triceps brachii. This exercise is performed with a dumbbell. The concentric portion of the lift is elbow extension, which involves the lifting of the weight. The eccentric portion is elbow flexion, which involves the descent of the weight.

The purpose of the cross body triceps extension is to strengthen the triceps while promoting hypertrophy (increases in size) of triceps.

Cross body triceps extensions provide a variation in exercises that activate the triceps brachii. It is also a variation of the lying, standing and seated triceps extension exercises, providing a different angle of triceps activation as the elbow flexes and extends across the body.

The lying position of cross body extension helps isolate the contraction of the triceps, focusing on one arm at a time. The shoulder positioning and neutral grip places emphasis on the lateral head of the triceps. The lateral head of the triceps makes up the outer portion of the “horseshoe”. Increasing the size of the triceps lateral head improves the overall aesthetics of the triceps muscle.

Cross body triceps extensions strengthen and increase the size of the triceps brachii. Cross body triceps extensions also serve as an auxiliary exercise that can increase strength involved in other multi-joint exercises.

The triceps brachii is located on the back of the upper arm, originating at the shoulder and inserting in the elbow joint. It consists of three heads, the long, medial and lateral head. The medial head lies beneath the long and lateral head. The long head origin is located at the infraglenoid tubercle of the scapula (shoulder blade). The original of the lateral head is located at the posterior shaft of the humerus. The medial head origin is located at the radial groove of the posterior humeral shaft.

The long and lateral heads make up the “horseshoe” portion of the triceps. All three heads merge, sharing insertion into the olecranon process of the ulna, located at the elbow joint.

The triceps brachii extend the elbow joint. The long head assists in arm adduction.

The anconeus is a short, triangular muscle located at the elbow joint. Its origin is located at the lateral epicondyle of the humerus, inserting at the lateral aspect of the olecranon process of the ulna.

The positioning of the shoulders in a flexed position requires the deltoids and rotator cuff muscles to ensure stability of the joint capsule throughout the movement.

One-arm cable elbow extensions.

Focus on the concentric portion of the contraction, concentrating on “squeezing” at the end of the flexing portion.

Emphasis on eccentric contractions, prolonging the eccentric portion of the contraction, may also be incorporated in a training program focused on increasing strength. This should be implemented accordingly and with adequate muscle recovery as eccentric contractions cause substantial damage to muscle tissue.

Strategically performing variations of this movement with a cable crossover machine (one-arm elbow extensions) at different angles and grips may improve performance with dumbbell cross body triceps extensions over time.

It’s important to note that your repetition and set volume will depend on your goals (e.g. strength, hypertrophy, muscular endurance). It is also important to allow adequate recovery days in between triceps and chest training to allow muscles to repair.

Bouncing the dumbbell at the bottom of the movement before the upward phase can result in elbow, triceps and/or shoulder injury. Therefore, it is important to control the downward and upward phases of the exercise.

Moving upper arm during exercise. The upper arm should remain stationary throughout the entire movement to isolate the triceps effectively.

If proper technique is not adhered to (e.g. dropping the weight quickly instead of controlling the descent on the eccentric portion of the lift, lifting a load too heavy for the lifter), the likelihood of injury increases.

Although rare, triceps tendon rupture and/or injury to rotator cuff muscles may occur if warm-up is not sufficient and/or if intensity (load) is increased inappropriately.

If proper technique and recovery are not adhered to, injuries such as impingement syndrome, rotator cuff injuries, and glenoid labrum tears may result.