The battle between pull-ups and chin-ups has been going on for a long time. There are famous defenders of both camps. For example, the author of Starting Strength Mark Rippetoe has been known for his chin-up affection while other gurus such as Pavel Tsatsouline prefer pull-ups.
Which one is easier on the joints?
People who do pull-ups often complain of wrist and elbow pain, mainly at the top of the movement. This is usually due to a narrow grip width and the implementation of a regular grip instead of the thumbless version.
When your grip is too close, there’s an overflexion of the elbow joint at the top of the movement that can result in strains. Also, when you wrap your thumb around the bar during pull-ups, your wrist is not aligned properly.
Wide grip chin-ups, on the other hand, do not cause as much elbow pain at the top, but they murder your wrists. Unfortunately, this problem is harder, if not impossible, to fix. Some people just can’t handle the pain, especially when the chin-up is done over a full range of motion (ROM). When doing chin-ups, stick to a shoulder width grip or even a little less than that.
Conclusion: Both, chin-ups and pull-ups, can cause similar amounts of pain. However, the problems with chin-ups are harder to soften.
Worked muscle?
Pull-ups – latissimus dorsi, upper back, rear delts, forearms, arm flexors with emphasis on the brachialis.
Chin-ups – latissimus dorsi, upper back, rear delts, forearms, arm flexors with emphasis on the biceps.
Conclusion: Chin-ups and pull-ups work similar muscle groups. The largest difference is that the former hits the biceps harder while the latter places more stress on the brachialis.
Which is better for muscle gains?
Both are perfectly fine, but ring-pull-ups tend to be more joint friendly. The reduced stress on the joint allows you to train with more volume and intensity, which could potentially lead to more mass gains.