You may baulk at the thought of trying to haul your body upwards from the floor and instead, by-pass the bar when at the gym to find something a bit less 'taxing'.
However, quash your fears and persevere, hoisting your own bodyweight from the floor is a great way to improve strength, body composition and confidence.
In this article we shall cover the following:
- Which muscles do pull ups and chin ups activate
- Why does the military use them
- Health and fitness benefits
- Strength curve
- Wrap up
Laypeople use the terms “pull-up” and “chin-up” interchangeably, but it turns out that they are two distinct exercises.
Pull-ups involve gripping the bar with the palms of your hands facing away from you while chin-ups require your palms facing toward you.
Supination and pronation (twisting inwards and outwards) of the arm during chin-ups and pull-ups changes the pattern of muscles worked. And this can have an impact on your long-term muscle size and strength goals.
The critical point is this: both exercises activate the same muscle groups, just to a different degree. Chin-ups put the emphasis on the biceps and chest, while pull-ups shift the focus more to the back.
In this article, we delve deeper into the differences between pull-ups and chin-ups. By the end of it, you’ll know why and how to incorporate each into your muscle-and-strength building routine.
Which Muscles Do Pull-Ups And Chin-Ups Activate?
Pull-ups and chin-ups are analogous to front squats and back squats. The muscle groups you activate are broadly similar, but the emphasis changes. And it’s this shifting pattern that keeps your body guessing and builds more rounded and functional strength.
Chin-Ups: Muscles Worked
During the chin-up, the primary movement is elbow flexion and shoulder extension in the sagittal plane.
Elbow flexion just means bending of the elbow. Shoulder extension in the sagittal plane means that the movement occurs along the axis of the body that runs from the feet to the head - the vertical direction. (Some movements, like lateral dumbbell raises, are a movement that occurs in the frontal plane, and abdominal twists operate in the transverse plane).
The type of joint flexion and extension tells us the muscles involved in chin-ups.
The primary groups targeted are the biceps brachii, latissimus dorsi, and posterior deltoid. Other targeted muscle groups include the brachialis, brachioradialis, teres major, and the spinal stabilisers.
- Biceps brachii: The biceps is one of the primary muscles in the upper arm and has two functions - to supinate the forearm (twisting anti-clockwise) and flex the elbow joint. During chin-ups, the palms remain supinated throughout the movement, so the biceps' job is to flex the elbow joint, bending the arms to bring the head up above the bar. The supinated position recruits muscle fibres in the long head of biceps more intensely compared to the non-supinated position used for pull-ups. People who effectively build the long-head often get a secondary bump on their biceps - something you occasionally see on some bodybuilders.
- Latissimus dorsi: The latissimus dorsi is a muscle that works to adduct (draw in) the shoulder joint and allow rotation of the arm. During chin-ups, it contracts to rotate the shoulder in the frontal plane, bringing your elbows towards your hips. Activation of the muscle is considerable during chin-ups and roughly as high as pull-ups.
- Posterior deltoid: The posterior deltoid is a muscle at the back of the shoulder that allows it to rotate in the transverse plane. It is what allows you to bring the elbow behind the body when you perform a seated row. The body automatically recruits the posterior deltoid during chin-ups to keep the shoulders rotated backwards throughout the movement. It is assistive, meaning that it kicks into action the moment you start the exercise.
- Brachialis: The brachialis is the muscle in the upper arm that sits underneath the biceps and is the principal mover whenever you flex your elbow. If you were to strip away the biceps, you’d see the brachialis underneath as a pear-shaped muscle that connects the front surface of humerus (upper arm bone) to the ulna (lower arm bone). The muscle doesn’t get as much air time as the biceps, but when you build it, it increases the overall volume of the upper arm considerably. The best isolation exercises that target the brachialis are variations on hammer curls which involve pronation as part of the exercise. In chin-ups, the hands are pronated, which helps to work the brachialis more intensely than regular pull-ups.
- Brachioradialis: The brachioradialis is a ribbon-like muscle that connects the humerus in the upper arm to one of the bones in the forearm called the radius. When the muscle contracts, it pulls the forearm towards the upper arm and works in synergy with the biceps and brachialis. Chin-ups use the brachioradialis to a lesser degree than pull-ups because there is less supination of the forearm. However, the body still recruits it as a stabiliser muscle.
- Teres major: The teres major is a muscle that sits deep in the shoulder joint, close to the scapula. Its purpose is to stabilise the shoulder joint. During chin-ups, the body uses it to pull the upper arm backwards and to the side of the body and ensure that the arms remain internally rotated. If you are lean and have trained the teres major, you can sometimes see evidence of the muscle below the rear deltoid and above the latissimus dorsi. Like the posterior deltoid, it is an assistive muscle.
- Other stabilisers: Chin-ups also activate the abdominals and spinal stabiliser muscles to prevent the body from swinging around during the exercise.
Pull-Ups: Muscles Worked
Since pull-ups are similar to chin-ups, they work similar muscles. However, the degree to which they activate muscles differs.
- Biceps brachii: Just like chin-ups, pull-ups activate the biceps substantially. However, because the wrists are in a supinated position, the exercise places more emphasis on the short head of the biceps. Thus, bodybuilders who wish to target the short head of the biceps should incorporate this movement into their routines.
- Latissium dorsi: The activation of the latissimus dorsi is high for both chin-ups and pull-ups. However, data from studies measuring nerve signal intensity during exercise found that activation of the lats was slightly higher for pull-ups than chin-ups. Thus, bodybuilders will sometimes recommend pull-ups over chin-ups for developing a wider back.
- Posterior deltoid: As with chin-ups, the body recruits the posterior deltoid as a stabiliser muscle to prevent transverse movement of the shoulder joint during the exercise. Again, the pull-up movement recruits this muscle in synergy with the others, enabling the trunk of the body to move upwards towards the bar.
- Brachialis: As discussed, pull-ups activate the brachialis, but not to the same degree as chin-ups.
- Brachioradialis: During the pull-ups, the body recruits the brachioradialis to a greater extent than during chin-ups due to the supinated position of the forearms. As the elbow flexes, it recruits the biceps, brachialis and brachioradialis to a significant extent.
- Teres major: Pull-ups activate the teres major slightly more than regular chin-ups because of the additional moment forces from the wider grip. Again, the body uses the muscle to stabilise the core during movement.
- Stabiliser muscles: Due to the slight change in the angle of the body, pull-ups activate core stabiliser muscles differently from chin-ups. There is slightly more activation of the abdominals since the supinated forearm position brings the angle of the body further away from vertical.
Whenever you are trying to gain strength and size, subtle variations in muscle activation are welcome. Hitting muscle groups from different angles helps to develop roundness, fullness, and thickness and keeps the body guessing. Thus, any complete strength and muscle program should include both movements interchangeably for maximum effect. Each will target the major muscle groups of the arm and upper back. And both will help to build size, especially if you switch from one to the other every couple of weeks.
If you want to increase the level of intensity you can wear a weighted vest, use a ruck sack with weight or wear a special belt which uses a chain to loop through a weight plate,
Sometimes you will read that pull-ups and chin-ups are good exercises for building your upper chest. This claim is partially valid. Both exercises activate the upper chest to maintain the position of the shoulder joint (similar to the rear deltoid). Still, the contractions and force on the muscle are minimal, so you’re unlikely to see an increase in size, independent of any chest-specific exercises you do.
Alternatives To Pull-Ups And Chin-Ups
There are a variety of reasons you might not want to do pull-ups and chin-ups.
- You’re not able to perform full pull-ups and chin-ups because you don’t have the upper body strength to raise yourself throughout the full range of motion unassisted.
- You have injuries that prevent you from performing the movement.
- You want to vary your exercise routine to keep your muscles guessing.
Fortunately, several alternative exercises broadly work the same muscle groups. Let’s take a look at them now.
If you haven’t trained before, it's unlike that you will be able to do a full set of pull-ups or chin-ups unassisted. If you can, it is a sign of a naturally athletic physique.
Similarly, if you are carrying a few extras pounds (or kilos), that too will make doing full pull-ups and chin-ups more challenging. The added weight adds to the difficulty.
Most gyms nowadays have an assisted pull-up/chin-up machine. Here you kneel on a tray that pushes up on you throughout the movement, making it more manageable. You can adjust the level of assistance, making the pull-up easier or harder.
If you’re severely overweight and looking to get back into shape, you’ll want to set a high level of assistance to start. If you’re closer to being able to do a full pull-up by yourself, you can set the level of assistance lower so that you’re just able to complete a set.
Assisted pull-ups/chin-ups are a great way to get your body used to the motion of the exercise. Some people find that after just a couple of sessions on the assisted pull-up machine, they’re able to perform the real thing without any help at all. Often, it is just a case of training the nervous system to get the muscles to fire in the right way.
Lat pull-downs are another machine-based exercise, except this time, you’re in a seated position and pull down on a bar connected to weights via a cable.
Lat pull-downs are probably the most common alternative to traditional pull-ups and allow you to adjust the weight, so that it is proportionate to your strength. In many ways, it is more versatile than the assisted pull-up machine because it allows you to lift more than your bodyweight. You can set the stack and high as it will go, anchor your knees beneath the padded restraint and take your back training up a notch, without having to use a weighted belt.
A great variation of the lat pull down is to incorporate the knees.
Yes, known as the knee lat pull down, you simply kneel on the floor where the bench to sit on would be positioned and pull the handle downwards. This activates the same muscles as a normal pull up.
You’ll often hear people say that using machines isn’t as effective as bodyweight or free-weight exercises. But, again, you should take claims like these with a grain of salt. Remember, strain, fatigue and tension are the only things that muscles care about. Fundamentally, they have no idea whether you’re doing a bodyweight chin-up or a lat pull-down with the same level of resistance. All muscles can do is contract.
As before, variety is your friend. If you have the option, do both lat pull-downs and pull-ups.
Band pull-downs work similarly to the lat pull-down machine. But this time, the resistance comes from the elastic properties of the bands, not the force of gravity acting on the weight stack.
Band pull-downs are an interesting variation on the traditional pull-up/chin-up because the resistance varies during the exercise. The movement gets progressively more challenging as the bands extend, and easier as they contract.
Rowing Movements With Elbows Tucked In
If you’ve injured your shoulder joint or don’t have access to any of the equipment discussed above, rows are your next-best option for building muscle in the arms and back.
Like pull-ups and chin-ups, rowing movements operate in the sagittal plane. But instead of pulling vertically, the movement is horizontal to the ground. Most people use a cable machine to simulate a movement to rowing in a boat. You’re pulling low towards your torso, activating many of the muscles in the back and arms.
If you don’t have access to a rowing machine, you can perform bent-over dumbbell rows for similar results.
Rowing movements activate the same muscle groups as pull-ups and chin-ups (namely the latissimus dorsi, trapezius, biceps and rhomboids), but to different degrees. Rows target the rear deltoids and muscles between the shoulder blades more because the movement primarily involves flexing the shoulder blades together. Pull-ups and chin-ups target the latissimus dorsi more - the muscle responsible for achieving a classic V-shaped torso - because it primarily involves lateral rotation of the shoulder joint.
Pull-overs are an excellent alternative to pull-ups and chin-ups if all you have available are dumbbells. As with the other exercises, you’re free to adjust the weight so that it is just challenging enough to tax your muscles, but not too heavy to risk injury.
Lay on your back on a bench and then clasp the weights attached to the dumbbell with your palms facing upwards. Bring the dumbbell behind your head and then rotate the shoulders to lift it back over your head towards your chest.
You should find that the movement activates the lats and the chest. Be sure to keep your arms strength so that you can maximise tension on your muscles as you raise and lower the weight.
Why Does The Military Use Chin-Ups And Pull-Ups?
For years, people have associated the chin-up and pull-up with the military. Films and TV series portrayed angry sergeants drilling exhausted recruits with the exercise, making the movement mainstream. However, it’s not all about bravado. There are good reasons why the military makes recruits do them.
The army describes pull-ups and chin-ups as “evidence-based exercises” that officials can use to assess the condition of troops. They’re a powerful signal that a person is in good physical shape.
Think about what being able to do a pull-up or chin-up demonstrates. It shows that a person has both upper body strength and leanness.
Some recruits might be physically strong. But the military wants to know whether they are powerful in relation to their weight. Being able to do a pull-up or chin-up suggests that they are.
According to military standards, women should be able to do around twelve unassisted pull-ups, and men between eighteen and twenty-three, depending on their age. Today, the issue has become more contentious as women enter the marine corps. Differences in standards have created division in the ranks.
The requirement for chin-ups in the military dates back to WWII when they first became part of the fitness requirements.
The Health And Fitness Benefits Of Pull-Ups/Chin-Ups
We know that pull-ups and chin-ups help build strength and muscle size. But what are the specific health and fitness benefits you can expect from doing these exercises?
Improved Grip Strength
While trainers traditionally associate pull-ups with back and arm training, it is great for grip strength too. Research reveals that practically all variations of the movement increased voluntary muscle contraction force in the hands.
Pull-ups increase grip strength in the same way as bowling and rock climbing can. Read how rock climbers have good pull up strength, here.
When you grip onto the bar, you exert sufficient force to keep your hands clenched. Training of grip muscles is isometric, but it can still build strength long-term.
On attempting a set of pull-ups or chin-ups, some people find that their grip strength is their weak point. They’re perfectly able to lift their body using their major muscle groups. But their grip can fail them part-way through their set.
The best way to improve grip strength is through continued practice. As you train, the muscles and nerves in the forearm become accustomed to gripping harder. Eventually, you’ll get to the point where the forearm is no longer the limiting factor.
Reduced Visceral Fat
Visceral fat is a dangerous type of fat that sits around your organs. Unlike subcutaneous fat (adipose tissue immediately beneath the skin), research strongly associates it with metabolic diseases, such as non-alcoholic fatty liver, type II diabetes and heart disease.
Evidence, however, suggests that regularly performing resistant and strength training exercises helps to radically improve your health by reducing visceral fat and increasing muscle insulin sensitivity. It may also have beneficial action for chronic pain conditions, such as fibromyalgia.
Improved Mental Health
Because pull-ups are compound movements that recruit a large percentage of the body’s skeletal muscles, they can have profound effects on mental health. Just like squats and deadlifts, the pull-up activates a considerable proportion of the body’s muscle tissues, making it a powerful tool you can use to access some of the proven mental health benefits of strength training.
A review published in the American Journal of Lifestyle Medicine, for instance, found multiple benefits from regular strength training, including reduced anxiety, lower incidence of depression, improved self-esteem and reduced feelings of fatigue.
Increase Your Training Intensity
Pull-ups and chin-ups are challenging exercises. The absence of any assistance means that you can’t rely on machines to do the work for you. You either have the strength to perform them, or you don’t.
It is easy to get into the habit of lowering the weight on the lat pull-down or increasing the assistance of the assisted pull-up machine. But that can stall your progress.
Research tells us that if you do not use or challenge our muscles, they won’t get stronger. For this reason, unassisted pull-ups are an excellent exercise for people who want to imbue their training routines with more discipline.
Remember, the purpose of training is to avoid plateauing. Doing traditional pull-ups could be precisely what your body needs to spur it to the next stage of growth.
Improved Overall Fitness Level
Pull-ups and chin-ups are challenging movements that put tremendous demand on your cardiovascular system. Doing them correctly requires recruiting practically all of the major muscle groups in your upper body.
When you do this for the first time, you’ll notice that you quickly feel out of breath. After a set of ten or twelve reps, you’re panting as your cardiovascular system attempts to repay the oxygen debt.
The experience is a little unpleasant, but it is also a sign that you’re getting a good workout. Studies reveal that regular strength training can dramatically enhance your body’s ability to turn oxygen into energy, improving your overall cardiovascular fitness and stamina.
Improved Muscle Strength
Both chin-ups and pull-ups increase muscle strength over time. During the first couple of months of training, the body routes new nerve endings to the muscle fibres so that you can consciously activate more of the muscle already present. Then, once it exhausts the gains from that process, it begins to increase the physical size of the muscle fibres, directly adding to contractile force potential.
Exercises such as the pull up are recommeded for developing strength and improving posture as outlined by the UK's National Health Service, here.
Pull-ups activate the lats more, while chin-ups focus more on the biceps and the muscles between the shoulder blades.
If you can’t do a full dynamic pull-up (where you actively lift yourself to the bar before lowering down again), you can ask a training partner to help you perform the negative part of the movement. Get them to lift you into position above the bar, and then lower yourself down slowly, resisting gravity as you go. If you are strong enough, you should find that you can control the speed at which you descend. In some cases, you may be able to hold yourself in the same position for several seconds. Both static holding and controlled descent help to increase muscle strength, bringing you closer to being able to do a full pull-up.
The Strength Curve For Pull-Ups And Chin-Ups
When you first get into chin-ups and pull-ups, the entire movement feels challenging. But as time passes, you find that the most difficult part is the latter section as you move your head above the bar.
Don’t worry: this isn’t evidence of muscle imbalance. Instead, it’s a function of the way that muscles work.
The contractive potential of muscles is typically higher when they are in their extended position. At the bottom of the pull-up (when your arms are dangling from the bar), your major muscles are at their longest. As you begin the lift, they begin shortening. And right at the top of the movement, they are at their most compact.
The strength curve is bell-shaped for pull-ups - as it is for the majority of movements. At the bottom of the lift, you have the least strength. Then as you move through the middle, the contractive force your muscles can exert increases, before trailing off again at the top.
You will often find that raising your body using your arms and back is easy until you want to touch your chest to the bar. Then, things get very challenging.
The reason for this is that the largest muscles in the back - the lats - can’t rotate the shoulders back to push out the chest. Instead, you have to rely on smaller muscle groups to facilitate the motion. And they don't usually have the required strength.
Thus, failing to touch the bar with your chest is not a sign of muscle imbalance or lack of strength. Instead, it is an artefact of your body’s biomechanics. Over time, you’ll find that you can get closer to the bar as you develop the supporting muscles. But there is no reason to complete such an extreme range of motion to get the benefits of pull-ups.
Stretching Between Pull-Up And Chin-Up Sets - A Good Idea?
When you finish a set of pull-ups or chin-ups, you have a choice. Either you can let go of the bar and rest how you would usually, or you can hang from it and stretch your muscles.
You’ll notice that when you relax after a set of pull-ups, your shoulder blades extend and the whole upper body feels more relaxed. Getting out of this position is challenging, which is why most people only enter it at the end of a set, rather than between each rep.
Some evidence suggests that stretching between pull-up and chin-up sets can increase the effectiveness of training by putting additional tension of muscles. It could be that the stretching action sends more signals to muscle cells, telling them that they need to grow and adapt than dynamic movement alone.
However, the jury is still out on whether so-called “interset stretching” is beneficial. While it may increase muscle activation, it could adversely affect subsequent set performance, reducing overall training volume.
Variations On Pull-Ups And Chin-Ups
Pull-ups use an overhand (supinated grip) while chin-ups use an underhand (pronated grip). But there are variations of both which you should explore as part of a comprehensive strength and muscle-building program.
You might have noticed that some bars on the lat pull-down machine have a bend in them at the edge. The purpose of this is to allow you to perform lat pull-downs that put less strain on your wrists while still engaging the large muscles in your back.
Some gyms have pull-up bars with angled ends in both wide and narrow grip varieties. However, equipment like this is relatively rare.
Unlike pull-ups (where your palms face away from you) or chin-ups (where your palms face towards you), neutral-grip pull-ups are where your palms face each other.
If the only equipment you have is a bar, you can perform neutral grip pull-ups by standing directly underneath it and clasping your hands together from either side. Another way to do it is to find parallel rails.
Neutral grip pull-ups are an excellent option for people who want to get the muscle activation benefits of both pull-ups and chin-ups in a single exercise. Finding equipment that allows you to perform the movement, however, can be a challenge.
Rotating Ring Grip
Lastly, gymnastics rings are an excellent tool for people who want to allow the arms to rotate as they pull themselves up. This piece of equipment recruits more stabiliser muscles, making it more challenging than fixed apparatus.
You may have also heard these called 'kipper' pull ups.
This variation stems from CrossFit. If you want to perfrom this version, some further guidance would be required.
Unlike the strict pull up/chin up which requires you to haul your body upwards and then lower yourself, the kipping pull up requires the use of your hips, in effect you use momentum to swing your body upwards in order to perfrom the most in the least amount of time...or within a strict time frame for competition.
Needless to say, these will not sufice as pull ups for military assessments.
In summary, pull-ups and chin-ups are two similar exercises that target broadly the same muscle groups. The only difference is in the way you grab the bar. With pull-ups, you take an overhand grip with your palms facing away from you, while with chin-ups, you adopt an underhand grip with your palms facing towards you.
Both exercises are beneficial in your training program, and neither is better than the other. Including each of them gives your muscles maximum stimulation, creating a more balanced physique.
This post was written by Ben - BA(Hons).