Lateral Bicep Curl

The lateral bicep curl is a dumbbell isolation exercise in which the arms are raised out to the sides at roughly shoulder height and the elbows bend to curl the weight toward the shoulders. Raising the arms laterally shifts more of the workload onto the biceps brachii and recruits the shoulder stabilizers to hold the arm in position throughout the set. It is a straightforward accessory movement for building arm size and definition and pairs well with standard curls in an arm-focused routine.

Muscles Targeted

• Primary: Biceps brachii
• Secondary: Brachialis, brachioradialis
• Tertiary: Anterior and medial deltoids, forearm flexors

Starting Position

Stand with your feet shoulder-width apart, holding a dumbbell in each hand. Raise both arms out to your sides until they are roughly parallel to the floor, palms facing forward, with a slight bend in the elbows. Keep your shoulders down and your core braced so your torso stays still once the movement begins.

Execution Steps

1. Set your upper arms in the raised, laterally extended position and hold them still for the entire set
2. Curl the dumbbells by bending your elbows and bringing the weights up toward your shoulders
3. Squeeze your biceps at the top of the movement, keeping your upper arms improved rather than dropping them
4. Pause briefly at peak contraction
5. Lower the dumbbells under control back to the raised starting position without letting your upper arms drift downward
6. Repeat for the desired number of repetitions, maintaining the lateral arm position throughout

Form Cues

• Keep the upper arms improved: The shoulder angle should stay fixed near horizontal; only the forearm should move
• Curl with the biceps, not the shoulders: Avoid using shoulder momentum to help lift the weight
• Move at a controlled tempo: Fast, jerky reps reduce time under tension and increase strain on the elbows
• Keep wrists neutral: Avoid excessive wrist flexion or extension during the curl
• Brace your core: A stable torso prevents compensatory swaying as your arms fatigue

Common Mistakes

• Letting the upper arms drop: Allowing the arms to fall toward the sides during the set turns this into a standard curl and reduces the intended lateral emphasis
• Using momentum: Swinging the dumbbells or using body English to move the weight reduces biceps activation and raises injury risk
• Going too heavy: The raised-arm position is inherently less stable, so excessive weight quickly breaks down form
• Partial range of motion: Stopping short of full elbow flexion or extension reduces the training stimulus
• Flaring the elbows excessively: Letting the elbows travel too far behind the shoulder plane stresses the shoulder joint unnecessarily

Variations

• Standard dumbbell curl: Arms at the sides throughout, a more classic strength-building variation
• Hammer curl: Neutral grip throughout the curl, shifting emphasis toward the brachialis and forearms
• Cable lateral curl: Using a cable stack provides constant tension instead of gravity-dependent resistance
• Seated lateral curl: Sitting removes leg drive and body sway, isolating the arms further

Tips for Progression

• Add small weight increments (2.5-5 pounds per hand) once you can complete all sets with strict form
• Slow the eccentric phase to 2-3 seconds to increase time under tension
• Add a 1-2 second pause at peak contraction to intensify the biceps squeeze
• Progress from two-arm to alternating single-arm reps to increase focus and control

Training Notes

Use the lateral bicep curl as an accessory movement 1-2 times per week on upper-body or arm-focused training days, typically for 10-15 reps across 2-3 sets after primary pulling exercises. Rest 45-60 seconds between sets. Because the raised-arm position fatigues the shoulders as well as the biceps, keep the load moderate and prioritize clean form over heavy weight.