When I perform a pull up, I feel like I am lifting with my lats. But when I do a chin up, it literally feels like its all in my biceps. However, the mechanism still looks like it should be hitting other muscles too(lats, traps, abs, etc.)... And I feel like any exercise where you pull yourself up on a bar should target primarily your back muscles. Are chin ups hitting my lats or biceps(more)?
Chinups (palms towards you) do activate your biceps more, but not at the cost of your lats.
There's a bit of bro-science about pullups/chinups, but if you read a 2010 study in the Journal of Strength and Conditioning Research it tells a different tale. Basically, the recruitment of the latissimus dorsi is the same:
A general pattern of sequential activation occurred suggesting that pull-ups and chin-ups were initiated by the lower trapezius and pectoralis major and completed with biceps brachii and latissimus dorsi recruitment.
This is the recruitment range (via EMG results) for a pullup gadget, chinups, and pullups.
- Latissimus dorsi: 117-130%
- Biceps brachii: 78-96%
- Infraspinatus: 71-79%
- Lower trapezius: 45-56%
- Pectoralis major: 44-57%
- Erector spinae: 39-41%
- External oblique: 31-35%
Breaking muscle has a good article about it as well, which references the above study, and goes into more detailed discussion. The real distinction and benefit from pullups (palms away) over chinups (palms towards you) is related to shoulders, angles, and distance.
Something to remember about wide-grip, and realize that pullups are basically always wider than chinups, is that a wide-grip has a smaller range of motion. That's not necessarily a bad thing, but the impact on your shoulder is pronounced. If you were to widen all the way, you'd be (sort of) doing an iron cross, which is a tremendous load on the shoulder (just to put some context in there).
Depends on your grip, if you have close grip it will definitely target your biceps more, wide will hit your lats. However in saying, when I first started I had a similar issue as well, as fairy as it sounds, muscle mind connection will help you target your back. thinking about your lats working as you do your exercise will better engage them will completing. Look below about the grips (ignore the text, just pulled it from the net)