Bent vs. Straight Arm Lateral Raises: Which Builds Better Shoulders?

The shoulder is made up of three distinct heads of the deltoid muscle: the anterior (front), lateral (middle), and posterior (rear). Each plays a different role in shoulder movement and appearance. The anterior head helps lift the arm forward, the posterior head pulls the arm backward, and the lateral head raises the arm out to the side. It is the lateral head that creates width and roundness in the shoulder, and this is the part most directly targeted by lateral raise variations.

A training question many lifters run into is this: “Is it more effective to perform lateral raises with the arms bent at 90 degrees, raising the elbows out to ear level, or with the arms extended straight (with a slight bend) to the same height?”

Both movements may look similar, but they place stress on the shoulder in very different ways. More specifically, both versions target the lateral (middle) head of the deltoid, which is responsible for giving the shoulder its width and rounded appearance.

THE STRAIGHT-ARM LATERAL RAISE

When lateral raises are performed with arms nearly straight (a soft bend at the elbow), the mechanics are defined by a long lever:

• Torque: The dumbbell sits far from the shoulder joint, creating maximum torque.
• Muscle Load: The lateral head of the deltoid is heavily recruited, but lighter weights must be used to manage the long lever.
• Joint Stress: More stress on shoulders, elbows, and wrists, particularly if the weight is excessive or form breaks down.
• Perception: Often produces more discomfort in the joints than a strong, isolated muscle burn.

This style emphasizes isolation of the lateral head but comes with greater mechanical stress, making it best for lighter weights and controlled reps.

THE BENT-ARM LATERAL RAISE

With elbows bent at roughly 90 degrees, sometimes called a chicken wing raise, the mechanics shift significantly:

• Torque: The lever is shortened, reducing torque at the shoulder joint.
• Muscle Load: Still targets the lateral head, but allows heavier loads with less interference from stabilizers.
• Joint Stress: Friendlier on both the shoulder capsule and elbow joints.
• Perception: Produces a stronger mind–muscle connection and a more concentrated contraction in the lateral head.

FOREARM POSITION AND TRAP INVOLVEMENT

The position of your forearm during bent-arm raises changes which muscles assist in the motion:

• Forearms level, flat plane: When the forearms remain parallel to the ground as the elbows rise, the lateral head of the deltoid stays the prime mover. The traps are minimally involved.
• Forearms rotated downward, pouring the pitcher position: As the hands drop below elbow height, the shoulder internally rotates. This shifts some of the workload upward into the upper trapezius, which begins helping to elevate the scapula along with the deltoid.

Why this happens: The trapezius is a powerful elevator of the shoulder girdle. When the forearms turn downward, the humerus internally rotates, reducing the deltoid’s mechanical advantage and subtly recruiting the traps to finish the lift. This is why many lifters feel their neck and traps firing if they over-rotate the forearms or shrug during lateral raises.

WHY THE BENT VARIATION OFTEN FEELS BETTER

Even though the straight-arm raise generates more torque, many lifters report that bent-arm raises give a stronger contraction in the lateral head. This happens because:

• Stabilizers like wrists, forearms, and traps are not overburdened when forearms are kept level.
• Heavier weights can be handled more comfortably.
• Driving the elbows up in a flat plane keeps tension squarely on the lateral head.

WHICH SHOULD YOU CHOOSE?

Straight-arm raises are best for strict isolation of the lateral head, lighter weights, and higher-rep finishers.

Bent-arm raises are better for heavier work, joint safety, and developing overall delt mass by loading the lateral head effectively.

The most effective approach is to use both. Start with bent-arm raises for heavier sets and growth, making sure to keep forearms flat to minimize trap takeover, then add straight-arm raises to finish with isolation and a deep burn. Together, they provide a well-rounded path to broader, stronger shoulders.

COACHING CUES

• Keep your forearms level with the ground during bent-arm raises to prevent the traps from taking over.
• Focus on lifting the elbows rather than the hands to better engage the lateral head.
• Do not shrug your shoulders during the motion.
• Stop at about ear height to keep tension where it belongs.
• Use lighter weights for straight-arm raises to protect joints.
• Reserve heavier loads for bent-arm raises to safely challenge the delts.