Chapters
00:00 Myth #1: A supinated grip is best to train your biceps
02:27 Myth #2: You can train your biceps peak
04:22 Myth #3: You shouldn’t count back work as biceps training
05:36 Myth #4: Wide grip pulling exercises don’t train the biceps
09:59 Take-home messages
11:19 Outro
Transcript
The first myth is that it’s best to train your biceps with a supinated grip. For reference this is a supinated grip, as you would use during a chin up, this is a pronated grip, as you would use during a pull up, and this is a neutral or hammer grip, as you would use during, well, a hammer grip chin up. Intuitively, it feels like your biceps might be more active when you’re using a supinated grip, but what you’re feeling and what you’re seeing is the muscle being bunched up. Supination shortens the biceps, and we actually have multiple studies showing that the biceps grows more when it’s trained at longer muscle lengths. So in that sense, you might even argue that the biceps will grow more when you train it with a neutral or even a pronated grip. The reason some people think that it’s best to train your biceps in supination other than the feeling is because it has better leverage in that position. However, what we are concerned with for bodybuilding purposes, rather than when training for strength is not external force output, so we don’t care so much about the leverage, we care about the internal tension in the muscle, which is essentially the same as the internal force production, not how much of that internal force is translated into lifting a greater weight.
Longer muscle lengths are particularly advantageous for the biceps because, unlike many other muscle groups, the biceps are strongest both in terms of active and passive force contribution when they are at relatively long muscle lengths. Even when your elbows are at your side and your biceps are at a relatively long length already, as in the bottom position of a dumbbell curl or a barbell curl, fully supinating the biceps reduces its active and its passive mechanical tension because it puts the length below its optimal length for force production. Again, the reason that you are still relatively strong in supination is because of good leverage. And in some cases good leverage means that the body will recruit the muscle more and, therefore, generate more force and, therefore, have more mechanical tension and that leads to more muscle growth. However, in the case of the biceps we have multiple studies showing that grip width does not affect biceps recruitment, at least based on electromyography, for pull downs, pull ups, rows and biceps curls. So overall you definitely don’t have to just use a supinated grip for all your biceps work, in fact, it could very well be detrimental because you might get greater gains if you use a variety of forearm rotations including even some pronated work to lengthen the biceps more and really train it at maximal lengths.
Myth #2: You can train your biceps peak. The biceps is not just an elbow flexor. It crosses the shoulder. It even crosses the radioulnar joint at the forearm making it technically a tri-articular muscle which is relatively complex in structure compared to most muscle groups. Based on its role at the shoulder some people argue that training the long head, which is the rear part, the most elevated part, not the inner part, which is the short head, can be emphasized and by training the long head more you can increase the biceps peak. However, that probably doesn’t work because the role of the biceps at the shoulder is so trivial, it’s so weak that any functional differentiation between the heads is even more trivial. Many studies have looked at the role of the bicep at the shoulder and it’s hard to even find detectable muscle activity when you perform pure shoulder flexion, raising the elbow or moving the elbow to the side with abduction.
Technically, the biceps engages in both of those movements, it raises the elbow up to the front and out to the side, shoulder flexion and shoulder abduction, but the muscle activity levels are so low and the force production is so low that it’s really trivial for the purpose of stimulating robust muscle hypertrophy. Any differentiation between the ends because of the length and the angle of the short and the long head is a little bit different, causing slightly different effects on how much they contribute at various elbow and shoulder positions is really trivial. In practice the amount of biceps peak that you have is a function of just two factors: 1 – your genetics The shape of your muscle belly, the origin and the insertion points, just the overall shape of the muscle, that is by far the largest determinant of whether you have a big peaking biceps or a more long, elongated, more full biceps. And then, second is simply the total muscle size. So the best thing you can do to get bigger biceps peaks is simply just increasing the total muscle size. You just can’t emphasize the long head enough to meaningfully change the shape of the muscle belly.
The third biceps training this is that you should not count your back work or any indirect biceps exercises towards your biceps training volume. You absolutely should. Your biceps is trained with compound exercises. In fact, in the literature, on average, compound and isolation exercises or single joint and multi joint exercises are equally effective to stimulate muscle hypertrophy. A meta-analysis from 2023 by Rosa et al. found that indeed, on average, this is the case. However, it depends on the exact exercise. Just because on average compound and isolation exercises are equally effective does not mean that all isolation and compound exercises are equally effective.
Some exercises are, of course, more effective than others, regardless of whether they are in isolation or a compound exercise. For example: Chin ups are probably a really good biceps exercise. The biceps of a gymnasts certainly attest to this. However, dumbbell rows are not a great biceps exercise. We have direct research showing that dumbbell rows stimulate about half of the growth of biceps curls. So dumbbell rows should be counted approximately half as biceps training volume. Four sets of dumbbell rows will count as approximately two sets of biceps training volume. Pull downs in the literature also perform very well, which brings us to the next myth.
Biceps training myth #4 is that wide grip pulling exercises don’t train the biceps. They do. With very wide grip it is true that the biceps will be less involved because there’s less demand for elbow flexion and less range of motion in terms of elbow flexion. However, when you’re using a fixed implements like a barbell or a bar that you do pull downs on or anything that you grip for pull ups or chin ups, you have significant horizontal force production and this significantly increases the degree to which the biceps can help. By pulling inward into the bar or whatever implements you’re holding for a row or a pull up or a pull down, it makes it easier, biomechanically speaking, for the back muscles to perform the movement. Let me illustrate how this works with my amazing paint skills.
So here we have Hector. Hector is doing pull ups. And if you just look at vertical forces, then he is pulling from two sides, right? And it’s going straight down because it’s, that’s gravity. Gravity pulls straight down. Now, you wouldn’t be able to see how the biceps is involved at all because technically the axis of rotation, the elbow is directly below the hand. So there is no moment arm for elbow flexion. In reality, what’s happening is that the biceps, because the bar is fixed and you cannot move to bar the biceps is producing a horizontal inward force which is like this, which means that the total resultant force vector of pulling down on the bar, but also pulling inwards into the bar, creates a resultant force vector that goes somewhat like this. And now you see that the moment arm on the elbow is actually positive, because it’s directly perpendicular to your axis of rotation to the resultant force vector. So there is a positive moment arm for elbow flexion. And for the lats from shoulder, here we also have a resultant moment arm.
If you were only considering vertical forces it would be longer, you would think that it goes all the way from the shoulder to the elbow. The moment arm on the lats, and in general the back muscles that are producing shoulder adduction. This tells us two things. One, it explains why the biceps is involved at all and two – it means that biceps involvement, horizontal force production from the biceps on the bar reduces the moment arm for the back muscles, for the lats in particular. So the shoulder adduction moment arm. And that means essentially that the biceps and the back are working synergistically to lift the weight. Now that sounds super intuitive, right?
So one more time quickly to make sure everyone understands. Just looking at vertical forces, there would be no demands on the elbow and the moment arm would be like this, but that’s not the case, there is actually some horizontal force this way, which means the resultant force vector goes kind of like this, and there is actually an elbow flexion moment arm and an adduction moment arm like this. So the biceps involvement makes things easier for the lats. So based on the biomechanics we would expect that when you’re using a fixed implement like a straight bar, not with a dumbbell, the biceps will stay active even when you’re using a relatively wide grip. Indeed, based on the limited research that we have, the biceps seems to be well trained by something like wide grip pull downs.
A study by Gentil et al. found that a pronated wide lat pulldown stimulated as much muscle growth as a supinated grip barbell curl. Both exercises resulted in approximately 6% biceps growth and 10 to 12% strength gains, which was measured as isokinetic peak elbow flexor torque. We don’t have a lot of research on this and this is only one study. Moreover, it was conducted by Paulo Gentil who is a researcher from Brazil that has garnered a bit of a notorious reputation in the exercise science community for his affiliations with Matheus Barbalho who had a lot of his papers retracted for fraud. However, you have to be pretty crazy to risk your entire academic career to prove a point that pull downs are a good biceps exercise, I would think. Moreover, we do have another study lending some support to the equivalence of pull downs and barbell curls for the biceps, indirectly, at least, based on muscle damage. A study by Pompermayer et al. found that supinated shoulder width pulldowns and biceps EZ bar preacher curls stimulate a similar level of muscle damage in the biceps. So overall, this lends further credence to the idea that barbell curls and pull downs can be equally effective, and even with somewhat wider grips this may be the case.
All right, let’s wrap this up with some practical implications for your training. You don’t have to do all of your biceps training with a supinated grip. In fact, you probably shouldn’t. There’s probably some benefit to using a variety of grips, even some pronated work to stretch the biceps and really emphasize that potential stretch mediated hypertrophy or long length mediated hypertrophic effect.
Take home message #2: Don’t worry about your biceps peak. It is mostly a function of your genetics and simple total bicep size. However, that shoulder and elbow position do affect how effectively you can train your biceps. Specifically, you want your elbow at your side to lengthen the biceps. Because the biceps is active at the shoulder, even though it’s very weak, it does get shortened when you raise the elbow in any direction. So you’ll want your elbow at your side or behind your body when you’re doing your biceps training. Ideally, at least. This will lengthen the biceps, which will increase both active and passive force contribution, which should result in more mechanical tension and therefore more muscle growth.
Take home message #3: Compound exercises certainly counts towards your biceps volume to at least some degree. Some exercises, like dumbbell rows, are not very effective and should only be counted as approximately half towards your total biceps volume, but other exercises like pull downs, pull ups, and especially chin ups are very effective and should definitely be counted fully, even if you’re using a relatively wide grip.
All right. I hope this helps you get bigger guns. If you like this type of evidence based fitness content I’d be honored if you like and subscribe.
