If you want to build your biceps you would need to understand the anatomy and the biomechanics behind it.
The biceps is composed of two heads: long (outer) and short (inner) heads. Both heads joint together (inserts) into the outer bone of the forearm (the ulna). On top, both heads originate from two different locations. This is
fundamental if you want to fully develop your biceps. The tendon of the long head is attached on the top of the humerus which will come across over to the scapula. So the outer head of the biceps assists with arm flexion or lifting your arm in front of you. If you want to target this head you would need to position your arm behind the body. A good example is seated dumbbell curl on an incline bench. This is how you will place your long head into biomechanically strong position stretching the muscle and achieving maximum contraction.
If you want to target the inner head of the biceps and build width you will need to bring your arm in front of the body. That puts the long head into more relaxed position. To create event further length and tension of the inner muscle you would need to place your arm slightly outward as well. This is due to the muscle origin which is located in the coracoid process of the scapula. A preacher curl is a good example but you will need to supinate your hands i.e. rotate your palms upward. If you do the preacher curls with EZ bar you will target other muscles like brachialis and brachioradialis (which I will talk about in another article). If you want to target the biceps you will need to supinate more. I like to use dumbbells or T-bar. The same exercise can be done with the spider curl or bend over concentration curt. Another key to success is to avoid completely locking the elbow i.e. fully extending the arm. In that way, you will constantly maintain the muscle tension. This forces you to use the muscles as a brake instead of your ligaments and tendons.
In the next part, I’ll give you some training approaches and more coaching points on how to make your triceps bigger and stronger.