How the First Mr. Olympia Fixed His Weak Biceps

Chapters:

00:00 Intro

00:50 The MRI study: incline curls vs. preacher curls

01:10 Arm anatomy: biceps, brachialis, and brachioradialis

01:41 Study results: which muscles grew most?

02:06 Biomechanics and the limitations of standard curls

02:44 How preacher curls load the elbow flexors

03:50 Why incline curls favor the biceps

04:32 Choosing exercises for complete arm development

05:13 A preacher curl alternative without a preacher bench

05:41 Outro

Transcript:

The biceps of Larry Scott is perhaps the most famous biceps in the history of bodybuilding. Except, of course, Arnold Schwarzenegger. Yet, by his own account, Larry Scott’s biceps was a weak, lagging body part until he started training with Vince Gironda. Gironda also trained Schwarzenegger, by the way, and when Schwarzenegger met him, Schwarzenegger said, “I’m going to be the greatest bodybuilder that ever lived.” Gironda replied, “You just look like a fat fuck to me.”

Gironda was certainly a character, but his methods proved to be quite effective in the case of Larry Scott. Gironda said that he had lagging lower biceps development, so he said he should do preacher curls. It turns out that the functional anatomy there isn’t quite right, but it did actually work and we now know why, based on new MRI data. A new study had a group of untrained individuals train one of their arms with incline curls and the other arm with preacher curls. All other programming variables like volume and intensity were the same in both arms. Muscle growth was measured by magnetic resonance imaging, the gold standard. This is important because ultrasound cannot differentiate between the biceps and the underlying brachialis.

See, most bodybuilders only think of the biceps when they are training their arms or their elbow flexors. But in fact there are more elbow flexors. We also have the brachialis that lies underneath the biceps and is in fact the thing that pops up the lower biceps or what looks like the lower biceps, but is in fact the brachialis. There’s also the brachioradialis, which crosses over into the forearm and is sometimes considered more of a forearm muscle, but it is in fact an elbow flexor. You might be tempted to lump all of these elbow flexor muscles together and just treat them as biceps.

However, after 12 weeks, we saw that preacher curls resulted in significantly greater gains in the brachialis and the brachioradialis. Incline curls, however, led to the greatest gains in the biceps. Total elbow flexor growth was similar between the exercises. The brachialis lies underneath the lower biceps, so when it grows, it pops up the lower biceps. This explains why Gironda thought that preacher curls targeted the lower biceps. These gains are also exactly what you would expect based on the biomechanics. All of the elbow flexor muscles are strongest around anatomical position.

That means that when your elbow is straightened, your arm is straight and your elbow is at your side. That’s when the biceps and the other elbow flexors produce the most force and can be subjected to the most tension, so training them in this position has the highest potential for muscle growth. Yet this exact position is the position that is completely neglected by standard dumbbell and barbell curls. When you have your elbows at your side with a dumbbell or a barbell, gravity is pulling straight down, so there’s very little tension on the biceps. The bottom position is very easy.

Incline curls and preacher curls both solve this problem, but in a different manner. Preacher curls solve this problem by pushing the elbow forward. Resistance is now maximal when the forearm is horizontal, which is very close to the bottom position. You also readily feel this yourself. The bottom position is very hard and you experience very high tension in a relatively stretched position. However, the biceps is a triarticulate muscle. It crosses the shoulder as well.

This means that when you push the elbow forward, that shortens the biceps so you get more tension in the bottom position when the biceps is stretched at the elbow, but it is shortened at the shoulder, meaning that the total tension at longer muscle lengths isn’t actually that much greater. But for the brachialis and the brachioradialis, which don’t cross the shoulder, they do experience the most tension at long muscle lengths when they can produce the most tension, both active tension and passive tension.

So you don’t even have to believe in the whole stretch-mediated hypertrophy or “long length is better for muscle growth” story for this to be true. You simply have to believe that mechanical tension drives muscle growth, which is extremely strongly established in exercise science at this point. Incline curls don’t solve the problem for the brachialis or the brachioradialis, because in the bottom position, you’re still basically doing a standard curl. For these muscles, it doesn’t matter whether you’re standing up straight or whether you’re leaning back. They don’t cross the shoulder. So for them, it’s effectively the same exercise.

However, the biceps gets lengthened at the shoulder by leaning back. When your elbow is behind the body, you are stretching the biceps at the shoulder, so it’s at longer muscle lengths. And now, even though in the bottom position there’s still not much tension on the biceps, as soon as you start curling up the weight, you have high tension at relatively long muscle lengths. These biomechanics perfectly explain why incline curls are better for the biceps, whereas preacher curls are better for the brachialis and the brachioradialis.

Therefore, what I teach to students in my online certification course is that you need multiple exercises to fully target the elbow flexors. Standard dumbbell and barbell curls are just not optimal exercises. The holy trinity of biceps development is arguably preacher curls, incline curls, and of course, my baby, the Bayesian curl. All of these exercises subject the elbow flexors to high tension at long muscle lengths, just in slightly different manners. So what you probably want to do in terms of practical application is to have all of these exercises in your program at some point.

You don’t have to do all of them in every program, but these types of exercises are where you will probably get the greatest elbow flexor gains. For preacher curls, a practical problem for many people is that they either just don’t have a preacher bench or a Scott curl bench, and they also cannot do it with a dumbbell on a standard bench, because then the dumbbell hits the bench and they don’t get full range of motion. In this case, a good alternative is to do concentration curls in which you lean away from the dumbbell. Standard concentration curls, in which the upper arm is vertical, don’t have high tension at long lengths, but you can mimic the effect of the preacher curl by leaning back.

I hope this knowledge helps you get bigger arms. If you want to implement any of these exercises, you can find all of them in my MH Physique app, and you can get a two-week free trial with the link in the description. It should also be popping up in your screen right about now. See you next time.