Pull-Ups or Chin-Ups. What's the Difference?

by Hayden-William March 3, 2022

Time to Read: ~6 Minutes

Take Home Points:

Anatomy and biomechanics lead us to believe that the chin-up grip (palms facing you) will recruit the biceps to a greater extent than the pull-up grip.
Experimental studies comparing different grips are sparse.
Using EMG and motion capture analysis one group of scientists (Youdas et al., 2010) found that for a chin-up (palms facing you), your chest (pectoralis major) and arms (biceps brachii) are more maximally activated and for a pull-up (palms facing away from you) there is greater activation of your back muscles (specifically, infraspinatus and lower trapezius muscles).
EMG data from another group (Dickie et al., 2016) did not find the differences observed by Youdas et al.
Kleiber et al. 2015 found that the brachioradialis forearm muscle is more active in pull-ups than chin-ups.
Taken together, the limited evidence we have does still support differences in muscle contribution between pull-up and chin-up variations making both a useful addition to an upper body strength training program.

Background

When I train clients, a common question I get is, when performing a "pull-up", does the grip (orientation of the hands on the bar) matter? Specifically, they are asking the difference between having their palms facing away from them versus having their palms facing them. The palms facing away grip is generally known as a pull-up, whereas the palms facing you grip is known as a chin-up. You can see an example of each below:


Pull-Up (Palms Pronated)	Chin-Up (Palms Supinated)

So, what do we know about the differences, aside from the fact that they feel different when you perform them? Based on our understanding of anatomy and biomechanics the biceps muscle, biceps brachii, is likely more fully engaged in a chin-up whereas back muscles are likely more fully engaged in the pull-up. What do more detailed scientific studies say? I actually had a difficult time finding studies that examined differences during actual pull-up and chin-up exercises, but let's start with a closer look at one fairly comprehensive older study that did assess these differences – Youdas et al., 2010.

Highlighted Study

The Experiment:

Electromyography (EMG) was used to measure motor unit activity within muscles.
The authors compared the pull-up, chin-up and The PerfectPullup(TM) device, the latter of which we will skip for the sake of brevity.
7 muscles were examined with EMG – lower trapezius, latissimus dorsi, infraspinatus, erector spinae, pectoralis major, external oblique, and biceps brachii.
Motion analysis was combined with EMG data to link muscle activation to specific parts of the exercises’ range of motion.
21 men and 4 women in their 20s were used in the study.

The Results:

The lower trapezius and infraspinatus had greater activation in the pull-up compared to the chin-up.
The pectoralis major and biceps brachii had greater activation in the chin-up compared to the pull-up.
Differences in elbow joint sagittal plane range of motion between chin-ups and pull-ups were statistically ambiguous.

The Limitations:

The participants (the study sample) were heavily biased towards men.
The finish position for each trial had the participant just reaching their nose above the bar. Pulling such that the entire chin was over the bar or so that the bar touched below the clavicle (chest), would have been more challenging and might have resulted in different muscle activation patters. It is interesting that they did not take this approach given that they did try to compare elbow joint sagittal plane range of motion (which turned out to be statistically ambiguous).
The authors highlight some statistical differences in the text of their paper that do not match the indicators in the figures of the paper (which may be a result of clerical error).

Summary: As might be expected from anatomy and biomechanics, the chin-up variation used more biceps muscle and the pull-up variation used more back and shoulder muscle.

Additional Studies:

Since 2010, when the Youdas study was published, a few additional studies of note were published that examined grip differences:

Kleiber et al., 2015 (PMID: 26300781): Using 16 young adult motion capture and EMG measurements during voluntary isometric muscle contraction (not during actual pull-up/chin-up exercises), the authors found that the biceps brachii activation was constant regardless of prone or supinated hand position. However, the brachioradialis (a forearm muscle) was more active in the prone hand position.

Dickie et al., 2016 (PMID: 28011412): Using 19 trained males performing pull-ups and chin-ups, the authors didn't find the differences between pull-ups and chin-ups that the Youdas groups did. However, they found that standard pull-ups resulted in greater EMG activation of the trapezius muscle when compared to a neutral grip (palms facing each other) pull-up.

Ortega-Rodríguez et al., 2020 (PMID: 32669057): In trained males the authors found no difference in maximal strength, power, or reps to failure from pull-ups using a biacromial group (index finger in line with shoulders) or free width grip (grip with chosen by participant based on personal preference.

Final Thoughts:

EMG studies definitely have their limitations, among those are the varying ways scientists take their measurements. This may explain why the Youdas and Dickie groups had different results. More studies are definitely needed to present a clearer picture of muscle activation differences but the evidence we have so far from anecdotal observations, anatomy & biomechanics principles, and limited EMG data suggest that there are differences with the chin-up grip likely targeting your biceps a bit more and the pull-up grip targeting the brachioradialis and back muscles a bit more. As such, there is utility in using both grips in your upper body strength training.