Here's what you need to know...

  1. Research says the pull-up and chin-up are equally effective. When it comes to activating the lats and traps they both work.
  2. Grip width is more important. When it comes to recruitment of the lats, the distance between your hands is the most important factor.
  3. Grip orientation does matter for bicep activation. Chin-ups will recruit biceps more than pull-ups.
  4. Coach yourself with cues. The best way to activate your back muscles is to use proper form. There are two cues that will help you out.

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 vs. Chin-Up — Lats

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 Back

Pull-Up vs. Chin-Up — Traps

Some say chin-ups are better for the traps, but the only thing that matters in trap training is scapular movement. Grip orientation is completely irrelevant.

Let's look at that from an anatomical perspective. The main function of all three portions of the traps (upper, mid, and lower) are to retract the scapula. Also, the uppermost fibers elevate the scapula (like a standard shrugging exercise) and the lowest fibers depress the scapula (push your shoulder blades down toward the ground).

What does the research say? Researchers measured their subjects' traps in a study. They 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

Both heads of the bicep have the same main functions: elbow flexion with supination and forearm supination. Supination is present during the chin-up and not the pull-up. From an anatomical standpoint, the chin-up does appear to be better at hitting the biceps than the pull-up. Although, there's still elbow flexion occurring during the pull-up, meaning that the biceps are still under some stress.

What does the research say? 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.

Applying This to Your Workouts

You can effectively train the lats, biceps, mid, and lower traps with either the pull-up or chin-up. Although, a simple tweak in your pull-up or chin-up form can make far more of a difference than pronation and supination ever could. But to get the most benefit, you'll have to stick to strict pulling. One study found that there was significantly lower amounts of activity in the mid-traps, lats, and biceps during the kipping pull-up than in the other strict variations.

Increase Lat And Trap Activation

Unfortunately there are no studies measuring the effect that coaching has on muscle activation during these exercises. However, there is a study that examined the effect that cueing had on untrained athletes who were performing pulldowns. The study found activation of the lats was significantly higher after coaching than before.

Coach yourself. Here are a couple of cues that can dramatically increase the results you see from both the chin-up and the pull-up.

Chin-Up and Pull-Up Cues

1 – Chest to bar.

This will force you to extend your spine and anteriorly tilt your pelvis as you're extending your shoulder joints, which are also functions of the lats. So pulling your chest to the bar will cover three functions of the lats as opposed to one. When done correctly, pulling your chest to the bar will make your lats contract to the degree that they feel like they're about to cramp.

2 – Squeeze a tennis ball between your shoulder blades.

This cue will force you into retracting your scapula prior to initiating the pull-up. As you learned earlier, all three portions of the traps retract the shoulder blades.

If the above exercise looks familiar, it's because it is essentially the "sternum chin-up" which was invented by Vince Gironda. The Golden Age bodybuilders got a lot right when it comes to training.

Related:  Pull-ups: You're Doing Them Wrong

Related:  Real Women Do Pull-Ups

References

  1. Snarr, R. L., Hallmark, A., Casey, J., Nickerson, B., & Esco, M. R. (2015). Electromyographic comparison of pull-up variations. Conference paper.
  2. Snyder, B. J., & Leech, J. R. (2009). Voluntary increase in latissimus dorsi muscle activity during the lat pull-down following expert instruction. The Journal of Strength & Conditioning Research, 23(8), 2204-2209.
  3. Youdas, J. W., Amundson, C. L., Cicero, K. S., Hahn, J. J., Harezlak, D. T., & Hollman, J. H. (2010). Surface electromyographic activation patterns and elbow joint motion during a pull-up, chin-up, or perfect-pullup™ rotational exercise. The Journal of Strength & Conditioning Research, 24(12), 3404-3414.