Which is Better?Pull Up or Chin Up?Chin-up (For back) or pull ups benefits.

Chin-up (For back) or pull ups

Chin-ups refer to a supinated or underhand grip. Pull-ups refer to a pronated or overhand grip. There's been a lot of debate over which one is superior. People also like to argue about which muscles the two variations train. But there's really no need for debate. Anatomy and research has the answers.

Pull-Up or Chin-Up 

What hits the lats better? The main function of the latissimus dorsi is to extend the shoulder. Shoulder extension occurs during both the pull-up and chin-up.

The second function of the lats is to adduct the shoulder joint – drawing your upper arm down and in toward your torso. Most people who ignore this important function struggle putting width on their backs. It's because of this adduction function that the people who claim that wide grip pull-ups are better for the lats are correct, but not for the reasons they think.

Because of the adduction function of the lats, grip width has an impact on recruitment of the lats. Using a pronated grip can make it easier to perform adduction of the shoulder joint, but pronation and supination alone don't dictate the recruitment of the muscles of the back. Plus, the lower fibers of the lats take more of the load during shoulder adduction and the upper fibers take most of the load during shoulder extension.

Want to train your upper lats? Go with a close-grip chin-up. But if you're trying to hit your lower lats, a wide-grip pull-up is best.

What does the research say? Pulling variations hit the lats virtually the same. Two research teams examined muscle activation during pull-up variations. One looked at four different vertical pulling variations. Two of those variations were a pull-up (pronated) and a neutral-grip towel pull-up. They found that lat activity was nearly the same in both variations.

Another study compared three types of pull-ups: the standard overhand-grip pull-up, the chin-up, and the "perfect" pull-up (using pull-up handles that rotate). The amount of lat activity was virtually the same during all three movements.

Pull-Up or Chin-Up — Traps:

Researchers found that The traps were more activated during the standard pull-up than in the neutral pull-up. Other researchers found that lower trap activity was greater in the pull-up than in the chin-up. However, the researchers chalked this up to the pull-up requiring more effort from the lifter than the chin-up. More effort during could also explain why the other study revealed greater activity in the traps during the pull-up.

Pull-Up vs. Chin-Up — Biceps:

 One study found that bicep activity was far greater in the chin-up than in the pull-up. But it must also be noted that bicep activity was very high in all three variations – greater than 80% Muscle Voluntary Contraction.