How you draw arms depends on your experience level. So let’s look at the process of drawing arms across 5 levels of experience. This is also an interesting example of how to tackle any area of the figure based on where you are in your learning journey.

Total Novice

If you just started life drawing, I don’t think you need to learn anything specifically about the arm. All you need to do is try to draw what you see – that’s actually a big step.

One of the tools that you can use for that is seeing the negative space created by the arm against the torso.

Another skill to use is alignments. What in the torso is aligning horizontally with the elbow or the wrist?

So often, especially when an arm is off doing its own thing, it’s easy for the proportions to get messed up. You kind of zoom into that area and you’re just so focused on the arm that when you step back, you realize you’ve  drawn it three times longer than it should be relative to the rest of the figure. So simple measurements are really going to help. Things like, how is the length of the arm compared to the head length, or compared to the width of the torso?

To learn more about these basic observational skills, check out this tutorial on proportions.

Beginner Artist Stage

As you get a bit more experienced and you get into the beginner artist stage, now you can start to learn about some specifics about arms. But it’s still super simple.

The main thing I think you should keep in mind is that arms taper down. There’s a lot more muscle at the shoulder and the upper arm than there is at the wrist where it’s kind of bony and there’s tendons and stuff like that. And that means that it tapers down overall. Very often when I’m looking at beginner students drawings, that’s the feedback they’ll need.

I think it’s worth really noting the shoulder muscle called the deltoid at this stage as well. The deltoid is this teardrop shaped muscle and the fact that it comes down quite far on the upper arm is something worth noticing.

The deltoid comes down on the outside of the upper arm between the bicep and the tricep – so you don’t even need to get into the details of the bicep and the tricep yet, but just note that that deltoid shape is  coming down between the two.

For the rest of the arm, at this stage I think it’s useful to think about simple forms. So the upper arm is kind of a cylindrical shape. The upper forearm is also usually a cylindrical shape as opposed to the the wrist, which is very boxy.

If you can start to draw lines that wrap around the cylindrical form of the upper arm, wrap around the rounded form of the forearm near the elbow, and then boxy planes at the wrist, you’ll be doing really well with your arms.

Intermediate

Once you get into the intermediate stage you can start to really dive into anatomy. We’re going to think about three bones: the humerus, the ulnar bone and the radius.

First, let’s consider the humerus in the upper arm. We’re going to simplify it down to basically being a ball at the top for the socket with the shoulder, a cylinder at the elbow, and for the ulnar bone in the forearm, that’s basically going to be just a hinge on that cylinder.

So it’s really simple, it’s just a hinge.

Now, things get quite complicated when you realize that even though it’s this very simple hinging motion, the forearm can rotate over without the elbow moving. That is the other forearm bone – the radius – rotating over the ulnar. The ulnar actually isn’t rotating at all.

At this stage, you can also start to learn more about the muscles. For the upper arm, you can start to think about the bicep, the brachialis, the tricep and its three heads and its tendon.

1. the flexors, which start on the inner edge of the elbow and come out along the Palm side of the forearm
2. the extensors, which come out on the outer edge of that elbow and come out on the back of the forearm towards the back of the hand
3. the ridge muscles, which come out from the upper arm and run along the forearm towards the thumb. (The ridges muscles are the brachioradialis and the extensor carpi radialis longus).

If you can start to notice these things, you are really going to be doing well with your anatomy

At this stage, you may also want to relate your anatomical know-how to your gestural skills. But how does anatomy help you see the gesture?

Well, for one, because there’s more muscle in the upper arm compared to the lower arm, the arms taper. That’s very gestural, because there’s a direction to the taper and it provides movement and gesture to your drawing

Next, there’s asymmetry created by the muscles. If you have a straight arm, the tricep is going to be shortened and the bicep is going to be stretched out. The curve of the bicep is lower on the arm and the tricep curve will be higher on the arm, and so that creates this asymmetry in the curves which is really good for creating gesture.

When the arm is bent, the bicep is shortened and the tricep is straightened out, so again we have that asymmetry.

On the forearm, you’ll find that the flexors create a sort of long smooth curve from the elbow to the wrist, whereas those Ridge muscles on the other side of the forearm start on the upper arm and go over the elbow. Therefore their position is different and it’s a shorter curve –  it dives back into the forearm about midway on the forearm. This creates a strong asymmetry on the forearm as well

Having that bit of anatomical know-how really helps you see the gesture.  As you get more advanced, you’re going to see more and more of that anatomy and how it informs your gesture.

For example, you’ll start to see how those Ridge muscles wrap over the forearm when it’s twisted over. That twist will help you with your gesture as well.

You can start to round out your anatomical knowledge at this point. For instance, where before we may have just thought of the extensors as one group, now you could break it down into individual extensor muscles. But you don’t want to do that too early. It’s like if you go to the gym and you can lift 100 kilos, what would be the point of putting 300 kilos on the barbell? That would just be dangerous and definitely wouldn’t help you to be stronger. But putting 102 kilos on the barbell? That could be quite good. In short, you don’t want to bite off more than you can chew.

But once you are comfortable and familiar with everything I’ve mentioned up till this point, the you can start to look at individual extensor muscles, maybe even the individual flexor muscles, more of the intricacies or the tendons, and the little furrows that are created on the muscles. You can also round our your knowledge with other muscles like the anconeus, the pronator terrace, the coracobrachialis and complete your anatomical understanding.

Pro Level

So, what about expert level arms? Are we going even deeper into anatomy and rendering every single tiny little muscle? Well, maybe, if that’s what you’re into. But I think for a lot of us, the arm is just going to be part of a broader painting or drawing and it’s going to need to complement the design or the story we’re trying to tell. So all that stuff that we’ve studied about arms can help us do that. Even if you greatly simplify the arm and
you’re not using all that detailed anatomical know-how, just the simple curves that you use, the simple shapes that you use for the arm can still feel way more human when it’s informed by anatomy.

Little subtleties in how you draw the arm can make it so much more human. It’s not always about just rendering more and more anatomical know-how into your drawing, but using the anatomy to support the storytelling that you’re trying to do the composition, the design and so on.

If you enjoyed this article and want to  learn really simplified anatomy for the figure overall, the things that really matter, I would highly recommend our Fresh Eyes Challenge. Signing up also gives also gives you access to our really friendly supportive community and our free reference library as well – sign up here.

And finally, you can download my free PDF guide where you can see what skill level you’re at now and what skill level you need to work on next here