Dumbbell Single-Arm Preacher Curl

Overview

Target Muscle Groups:: Biceps.
Equipment:: Dumbbell, bench.
Difficulty:: Beginner.
Log Type:: Reps and weight.

General Information

Dumbbell Single-Arm Preacher Curl is an isolation exercise that primarily targets the biceps brachii, especially the short head. It also engages the brachialis to a lesser degree. This is a beginner-level movement known for its strict form and focus on muscle control.

By training one arm at a time, this exercise helps correct muscle imbalances and ensures both sides develop equally. The preacher bench supports the upper arm and eliminates momentum, making it easier to concentrate on the biceps contraction throughout the full range of motion.

Using a dumbbell allows for a more natural wrist and elbow path, which can be more joint-friendly than barbell variations. It’s a popular choice for hypertrophy training and for building the peak and detail of the biceps.

Instructions

Sit on a preacher bench and hold a dumbbell in one hand with an underhand (supinated) grip.
Position your arm against the angled pad so your upper arm is supported and fully extended downward.
Curl the dumbbell upward by flexing your elbow and squeezing your biceps.
Pause briefly at the top of the movement for maximum contraction.
Slowly lower the dumbbell back to the starting position under control.
Complete all reps on one arm, then switch to the other.

Common Mistakes

Rushing the movement

Performing reps too quickly reduces time under tension and increases injury risk.

Dropping the elbow

Letting the elbow move off the pad reduces bicep activation and compromises form.

Wrist bending

Allowing the wrist to curl or bend breaks alignment and reduces force transfer.

Using momentum

Swinging the dumbbell takes the focus off the biceps and can lead to poor results.

Injuries

Dumbbell Single-Arm Preacher Curl is a low to medium risk exercise when performed with proper form.

The fixed-arm position provided by the preacher bench helps minimize the involvement of the shoulders and back, reducing injury risk. However, using too much weight or extending the elbow too far at the bottom can strain the tendons around the elbow joint.

To reduce injury risk, avoid locking out your elbow and maintain a slight bend at the bottom of each rep. Use a moderate weight that allows for a smooth, controlled motion without jerking or swinging the dumbbell.

Frequently Asked Questions

Q: Is it better to do this exercise before or after barbell curls?: It works well as a finisher after heavier compound curls.
Q: Can I rotate my wrist during the movement?: No, keep your wrist fixed to maintain consistent tension on the biceps.
Q: Should I fully extend my arm at the bottom?: Lower the dumbbell until your arm is almost straight, but avoid locking out completely.

Overview

Target Muscle Groups:: Biceps.
Equipment:: Dumbbell, bench.
Difficulty:: Beginner.
Log Type:: Reps and weight.