Elbow flexors are comprised of four main muscles : biceps brachii, brachialis, brachioradialis, and pronator teres. To maximize hypertrophy, you need to train all four elbow flexors.
If you use the science of biomechanics wisely, you can bolster your arm growth. Here are some principles to go by:
1. To maximize arm growth you must develop every single elbow flexor: This means both heads of the biceps brachii, the brachialis, brachioradialis and pronator teres.
2. To do so, you must select the exercises and training methods best suited to do the job.
To work the short head of the biceps brachii, all curls where the elbow are forward to the body, such as concentration curls or Scott curls will do the job.
In order to recruit the long head of the biceps, all exercises where the elbows are behind the body, such as all the various forms of supine incline curls will do the job. The long head of the biceps responds very well to higher velocity movements.
To effectively recruit the brachialis and the pronator teres, all pronated forms of curls such as reverse curls will do the trick. If you isometrically pause for a two second at any point before reaching 90 degrees of elbow flexion, you will further activate the brachialis. The brachialis and pronator teres, are best activated by low velocity movements and isometric pauses.
To preferentially recruit the brachioradialis, use neutral grip curls, such as incline hammer curls.
3. Varying systematically the speed of contraction of your elbow flexors exercises will boost further growth.
For more tips building up the arms in size and strength read: