Although there are numerous variations of arm curl exercises, some are better than others. But there is no such a thing as a “single best” arm curl. A a variety of movements are necessary for complete development, and relying on only a few exercises can lead to overuse injuries and slower progress.
You’ll notice that there is only one barbell exercise on this list. Dumbbell exercises because they allow for more natural movements, work the muscles through a greater range of movement, and are superior for recruiting the higher-threshold motor units. Also – and this is a tip is credited to former Mr. Olympia Franco Columbu – dumbbells do not force the elbows and wrists into a locked position, which can place excessive stress on the joints and thus increase the risk of injury.
Whether using dumbbells or barbells, it’s best to use thick implements (dumbbells, 2 to 2 -1/2 inches; barbells, 3 inches). Thicker bars increase the training effect by activating more motor units and create tremendous increases in grip strength and forearm development.
With that background, here are the Top 10 most productive, “bang for your buck” arm curl variations.
1. Scott Reverse Curls
The Scott curl is usually called the preacher curl in the US. However, in most other countries, it’s called the Scott curl in honor of two-time Mr. Olympia Larry Scott, who slaved on it for years to develop his massive arms. This exercise is one of Scott’s favorites, because in addition to adding mass to the biceps it is also a tremendous forearm developer. Often biceps growth is limited by the development of the brachoradialis. This exercise corrects this weak link and as such can quickly promote tremendous growth in the biceps. Use an EZ curl bar to reduce the stress on the wrists.
2. Seated Dumbbell Hammer Curls
Hammer curls are performed with a semisupinated grip – as if you were holding a pair of hammers. This exercise has the advantage of shifting the overload in elbow flexion to the brachioradialis and brachialis at the expense of the biceps brachii. To prevent cheating, try resting your upper back against the chest pad of a Scott bench. Be sure to keep the position of your lower back fixed. The Atlantis Scott bench is excellent for this purpose because the footrest allows you to lock yourself into position.
3. Incline Dumbbell Curls
This is the most effective exercise for isolating the long head of the biceps. The incline position allows the elbows to be drawn back, away from the body, thus recruiting the long head. It was first popularized by Steve Reeves (’50s bodybuilder and Hercules movie actor) to give his biceps a godly look.
4. Seated Zottman Curls
This is one of the best upper arm thickening exercises because it thoroughly stresses all the elbow flexors. It feels uncomfortable at first, so it may take a few workouts to get used to this movement.
5. Standing Barbell Curl
Although EMG evidence suggests that Scott curls and incline curls recruit the elbow flexors more powerfully, this is still a great muscle builder and allows you to handle big weights compared to most other exercises for the biceps. To minimize cheating and maximize isolation, many coaches recommend pressing your back and gluteal muscles against a wall and having your elbows touching the sides of your torso. You can also use a 45- to 55 cm Swiss ball to brace your upper back.
6. Single-Arm, Offset-Grip Dumbbell Curls
An offset grip is an asymmetrical grip where the thumb side of your hand rests against the inside plate of the dumbbell. This will increase the involvement of the short head of the biceps. Start with the dumbbells in a semisupinated (hammer) grip and curl the weight to about 40 degrees. Then, turn your palm up (supinate) and complete the curl. Since you’re holding the dumbbell in an asymmetrical fashion, you’ll be forced to activate the short head of the biceps to complete the supination movement.
7. Single-Arm Dumbbell Scott Curls
While most biceps exercises require some assistance and stabilization work by other muscle groups, the Scott bench allows you to isolate the elbow flexors. By eliminating the possibility of using “body English,” you exclude the assistance muscles from participating in the movement. Most gyms have a standing Scott curl and a seated Scott curl; it’s best to use the seated version because it minimizes cheating.
8. Incline Modified Kettlebell Curl
Using a modified kettlebell is a good way to challenge the strength curve to make you stronger; you can get faster adaptations without suffering a strength plateau from doing the same thing for months on end. A modified kettlebell will spin so that it doesn’t stress the wrist or hit the forearm.
For example, if you do seated dumbbell curls with a modified kettlebell in which the center of mass is three inches below the handle, you have a different strength curve from what you would have when using a regular dumbbell where the center of mass is in line with the handle. With dumbbells, the point in the strength curve that is overloaded occurs much earlier in the motion than with a modified kettlebell. Just by changing the implement from regular dumbbells to kettlebells, you can trigger greater strength gains.
9. Concentration Dumbbell Curls
This is one of the most basic of all exercises. Its name comes from the undivided attention a trainee usually gives to the arm being worked; furthermore, it’s a physiological fact that you can increase muscle facilitation when you look at it.
The concentration curl can be performed in either a standing or a sitting position, but the seated kind is better. When you’re standing, your nervous system is partially distracted because it’s maintaining balance. Sitting down during this movement gives full attention to the curl and enhances neural drive.
10. Midline Hammer Curl
This exercise is a variation of the basic hammer curl. As you curl the dumbbells upward, bring them together in front of your sternum without allowing them to touch. Regardless of which of these exercises you decide to use right now, change them about every six training sessions so you don’t adapt. This will help ensure the greatest gains possible in the shortest amount of time.