Hammer Curl 1RM Calculator

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Hammer Curl Strength Standards (kg)

Body Weight Beginner Novice Intermediate Advanced Elite
120 kg 0 10 25 45 70
130 kg 0 10 25 50 75
140 kg 0 10 30 50 80
150 kg 0 15 30 55 85
160 kg 0 15 35 60 90
170 kg 0 15 35 60 95
180 kg 0 20 40 65 100
190 kg 0 20 40 70 105
200 kg 0 20 45 70 110
210 kg 0 25 45 75 115
220 kg 0 25 50 80 120

How to Perform the Hammer Curl

Stand with feet shoulder-width apart, holding a dumbbell in each hand at your sides with a neutral grip, where your palms face each other. Keeping your upper arms stationary and elbows close to your torso, curl the dumbbells upward by bending at the elbows. Maintain the neutral grip throughout the entire movement, without rotating the wrists. Squeeze at the top when your forearms are vertical, then lower under control to full extension.

Muscle Activation

The hammer curl shifts emphasis from the biceps brachii to the brachialis and brachioradialis. The brachialis lies underneath the biceps and, when well-developed, pushes the biceps up for a taller arm appearance. The brachioradialis is the largest forearm muscle and contributes significantly to arm thickness when viewed from the side. The biceps still contribute but are less active due to the neutral grip position.

Common Mistakes

  • Rotating the wrists during the curl, turning it into a standard dumbbell curl and reducing brachialis emphasis.
  • Swinging the body for momentum rather than using strict elbow flexion.
  • Not keeping the elbows pinned to the sides, allowing them to drift forward.
  • Performing reps too quickly without controlling the eccentric phase.

Variations

Cross-body hammer curls, where the dumbbell is curled across the body toward the opposite shoulder, increase brachialis emphasis. Rope hammer curls using a cable machine provide constant tension. Incline hammer curls performed on an incline bench increase the stretch at the bottom. Preacher hammer curls eliminate momentum entirely.

Programming Tips

Include hammer curls for 3-4 sets of 10-15 reps, 2-3 times per week. They pair well with standard bicep curls and can be performed in the same session. Hammer curls are also beneficial for improving grip strength, which transfers to pulling exercises like deadlifts and rows.

Frequently Asked Questions

Hammer curls use a neutral grip and emphasize the brachialis and brachioradialis, while regular curls use a supinated grip and target the biceps brachii more directly. Both are important for complete arm development.
Yes, the neutral grip heavily recruits the brachioradialis, which is the largest forearm muscle. Hammer curls are one of the best exercises for building forearm size and grip strength.
Yes, including both ensures complete arm development. Standard curls target the biceps peak, while hammer curls build arm width and thickness through the brachialis.
Most people can hammer curl about 10-15% more than they can strict dumbbell curl with a supinated grip, due to the mechanical advantage of the neutral grip position.

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