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Back exercisesBiceps exercises

Chin-up

Also called chinup, chin up, underhand pull-up, supinated pull-up.

What is a chin-up?

A chin-up is a bodyweight vertical pull from a straight-arm hang to the bar, using an underhand grip with your palms facing you. It trains the latissimus dorsi and other upper-back muscles together with the elbow flexors, including the biceps brachii. A pull-up uses an overhand grip; an assisted chin-up keeps the underhand movement but a band or machine offsets part of your bodyweight.

Two rear-view anatomical illustrations of a man performing an underhand chin-up on a fixed bar against a white background. In the left frame he hangs with straight arms and hands about shoulder width apart, the backs of his hands facing the viewer because his palms face him. In the right frame his elbows are bent beside his torso and his chin reaches the bar. His knees stay slightly bent and his feet overlap behind him in both positions. Red shading covers the latissimus dorsi along both sides of the back, the upper and middle back around the shoulder blades, the rear shoulders, and the upper-arm and forearm areas around the elbow flexors; the legs are unshaded.

How do you perform a chin-up?

Set up

  1. Use a stable step if the bar is out of reach, then take the bar with your palms facing you and your hands about shoulder width apart.
  2. Step clear and hang with straight arms, your feet off the floor and your body still.

Execution

  1. Begin the pull by drawing your shoulder blades down, then bend your elbows toward your sides.
  2. Raise your body until your chin clears the bar without kicking or reaching with your neck.
  3. Lower under control until your arms are straight again, let your body settle, and begin the next rep.

Common mistakes

  • Kicking or swinging to get over the bar

    Momentum changes the movement and makes one repetition hard to compare with the next. Stop the swing before beginning another strict rep.

  • Reaching the chin forward at the top

    Moving only the head can make it look as though the body reached the bar. Keep the neck comfortable and finish by lifting the body instead.

  • Dropping out of the top position

    A sudden drop removes control from the lowering phase and can restart the next repetition with a swing. Lower until the arms are straight and let the body settle.

Where it fits in a session

Early in an upper-body or pulling session, while the hands and elbow flexors are still fresh enough to hold the bar and keep each rep strict.

Use assistance when full bodyweight prevents a controlled repetition. Once bodyweight repetitions are repeatable, additional reps or a weighted variant can change the challenge without changing the underhand movement.

Muscles worked

Front
Front — Schematic surface view. Some muscles are partly visible or not shown.
Back
Back — Schematic surface view. Some muscles are partly visible or not shown.

Primary

Secondary

Select a muscle name to locate it.

Schematic surface view. Some muscles are partly visible or not shown.

The latissimus dorsi moves the upper arm and helps lift the body when the hands are fixed overhead. The biceps brachii, brachialis and brachioradialis bend the elbow, while teres major and the muscles around the shoulder blades assist the pull. The groups are not ranked within the primary and secondary lists: anatomy and the available chin-up research establish involvement, not a precise share of the work.

Scientific studies on chin-ups

Grip comparisons help explain how chin-ups and pull-ups share the workload. The studies below measured muscle activity during repetitions, so they cannot tell us which grip builds more muscle over months of training.

An underhand grip can change muscle activity, but it does not turn the chin-up into an arm-only exercise or establish a growth advantage over other grips. Choose a grip you can use comfortably and consistently; rotating handles have not shown a clear activation advantage in the comparison below.

Do chin-ups work the biceps more than pull-ups?

One study of 25 healthy adults found higher biceps and chest muscle activity during underhand chin-ups than overhand pull-ups. Lower-trapezius activity was higher with the overhand grip. That supports a change in emphasis, not a clean division into “arms” versus “back.”

A later study of 19 trained men compared underhand, overhand, neutral and rope grips. It reported broadly similar muscle activity over complete repetitions, with a clear difference for the middle trapezius between overhand and neutral grips. It did not establish a consistent biceps advantage for the underhand version.

The practical point is modest: grip can affect how a rep feels and which muscles contribute, but the results do not support a universal muscle-building ranking. Neither study measured long-term biceps or back growth.

What the measurements mean

Both studies recorded electrical activity at the skin and compared it with reference contractions. Dickie and colleagues analysed both peak activity and average activity, including separate lifting and lowering phases. A higher signal is not a direct measurement of muscle force or future growth. Our source review used the complete primary abstracts, so fine details of grip width, loading and technique were not independently checked in the full methods.

Do rotating handles add a proven benefit?

The 25-person study also tested a device with handles that turn during the repetition. It did not detect a clear difference in muscle activity between that device and ordinary chin-ups or pull-ups.

That gives little reason to expect extra muscle recruitment simply because a handle rotates. It does not show that all rotating handles or rings behave identically, and it did not test long-term growth, joint comfort or injury prevention. A comfortable hand position can still matter to your exercise choice without claiming a benefit the study did not measure.

Sources

Variations

  • Two frames of an anatomical illustration of a wide-grip pull-up, seen from behind, side by side on white. Left: the man hangs at full stretch from a bar fixed between two uprights, arms straight overhead, hands well outside shoulder width, palms facing away, knees bent and the feet tucked up behind him. Right: the top of the rep, chin level with the bar, elbows bent and driven down and out. Highlighted in red in both frames is the whole back of the pulling chain rather than one muscle — the fan of the latissimus dorsi down the ribs, the teres and rear-shoulder region under the armpit, and the muscles between and around the shoulder blades, which light up most strongly in the top-position frame. The backs of the upper arms are shaded too; the biceps and forearms face away from the viewer and cannot be seen, and the front of the body is not visible from this angle.
    Pull-upUses an overhand grip with the palms facing away instead of the chin-up's underhand grip.
  • Neutral-grip chin-up — Uses parallel handles so the palms face each other throughout the repetition.
  • Two rear-view anatomical illustrations of a man using a counterweighted assisted chin-up machine against a white background. In the left frame he kneels on the black assistance pad near the top of the repetition, with his elbows bent beside his torso and his chin close to the angled underhand handles. In the right frame the pad and his body are lower, his arms are straight overhead, and both knees remain on the pad. The silver machine frame and black weight stack are visible in both frames. Red shading covers the latissimus dorsi along the sides of his back, the upper and middle back around the shoulder blades, the rear shoulders, and parts of the upper arms and forearms; his lower body is unshaded.
    Assisted chin-upA band or assisted machine offsets part of your bodyweight; the standard chin-up does not.
  • Weighted chin-up — Adds external load with a belt, vest or securely held weight.
  • Negative chin-up — Begins at the top using a step or platform and trains only the controlled lowering phase.
  • Ring chin-up — Uses gymnastic rings, allowing the hands to rotate instead of staying fixed on a bar.

Articles

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Frequently asked questions

What muscles do chin-ups work?

Chin-ups train the latissimus dorsi and teres major as the upper arms move down toward the torso, the biceps brachii, brachialis and brachioradialis as the elbows bend, and the middle and lower trapezius and rhomboids as the shoulder blades move during the pull.

What is the difference between a chin-up and a pull-up?

Hand position. In a chin-up your palms face you; in a pull-up they face away. Both train much of the same back and arm musculature. One study found higher biceps activity in chin-ups, while another grip comparison found broadly similar activity across variations. Neither establishes which grip builds more muscle.

Are chin-ups easier than pull-ups?

Not for everyone. The underhand grip lets the biceps contribute strongly, which can make chin-ups feel more manageable for some people, but grip comfort, bodyweight and practice all affect which version feels easier.

Does your chin have to go over the bar?

Use the chin clearing the bar as a consistent top position, but reach it by lifting your body rather than stretching your neck forward. Keeping the same top and bottom positions makes repetitions easier to compare.

What if I cannot do a bodyweight chin-up yet?

An assisted chin-up preserves the underhand pulling pattern while a band, machine or partner offsets some of your weight. A negative chin-up starts at the top and trains the lowering phase. Both are variants; the standard chin-up in this guide moves your full bodyweight without assistance.

Sources

  1. Jeno SH, Varacallo MA. Anatomy, Back, Latissimus Dorsi. StatPearls. https://www.ncbi.nlm.nih.gov/books/NBK448120/
  2. Syros A, Rizzo MG. Anatomy, Shoulder and Upper Limb, Teres Major Muscle. StatPearls. https://www.ncbi.nlm.nih.gov/books/NBK580487/
  3. Tiwana MS, Charlick M, Varacallo MA. Anatomy, Shoulder and Upper Limb, Biceps Muscle. StatPearls. https://www.ncbi.nlm.nih.gov/books/NBK519538/
  4. Card RK, Lowe JB, Launico MV. Anatomy, Shoulder and Upper Limb, Elbow Joint. StatPearls. https://www.ncbi.nlm.nih.gov/books/NBK532948/
  5. Youdas JW, et al. Surface electromyographic activation patterns and elbow joint motion during a pull-up, chin-up, or Perfect-Pullup rotational exercise. J Strength Cond Res. 2010. https://pubmed.ncbi.nlm.nih.gov/21068680/
  6. Dickie JA, Faulkner JA, Barnes MJ, Lark SD. Electromyographic analysis of muscle activation during pull-up variations. 2017. https://pubmed.ncbi.nlm.nih.gov/28011412/

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