Protect Your Lumbricals While Pulling Pockets

The lumbricals are a series of muscles in the palm of your hand that run from the base of the fingers to near the wrist. Unlike most muscles, which attach to bone, the lumbricals attach to the flexor tendons of the hand. They don’t provide a ton towards finger strength, but they do provide stability and fine motor control.

Due to their structure, the lumbricals of the pinky and ring finger are prone to injury while pulling hard on pockets. They can also get injured when crimping or dragging with one, two, or even three fingers on small holds. When training and climbing, it’s important to be aware of how grip type can increase or decrease the risk of lumbrical injury.

So how does a lumbrical injury happen? Let’s use the common pocket-induced lumbrical injury as an example. When your hand is in a pocket grip, some of your fingers are extended (the ones in the pocket) while your other fingers are flexed inward towards your palm. In the pinky and ring finger lumbricals in particular, these different directions of force can cause a shearing action across the lumbrical which can strain or tear the muscle.

For example, when performing a two-finger pocket grip with your middle and ring finger, your pinky lumbrical—which is shared between your pinky and ring finger—is being pulled in two opposite directions. Your ring finger is extended and pulling one half of the lumbrical upwards while your pinky is flexed and pulling the other half of the lumbrical downwards.

There are two ways to pull on pockets, and there are pros and cons for each method. The first way is more dangerous to the lumbricals but it allows you to pull harder by engaging all four finger tendons. The second way is safer but produces less pulling force. To understand the differences between these two methods, let’s label our fingers. Our “inside” fingers are the ones in the pocket. Our “outside” fingers are the ones not in the pocket.

In the more dangerous yet stronger method, you flex your outside fingers deep into your palm. In the safer but less strong method, you do not flex your outside fingers fully into your palm. By keeping your outside fingers adjacent (or parallel) to your inside fingers, you help prevent the shearing force across the lumbrical. You can still bend your outside fingers to get them out of the way, but the sections of your outside fingers closest to your palm should remain parallel to your inside fingers.

Dr. Jason Hooper of Hooper’s Beta succinctly shows these two methods visually in the video below:

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A post shared by Dr. Jason Hooper, DPT, O/SCS (@hoopersbetaofficial)

If you’re new to pocket pulling, you should definitely start out with the safer method. If you’re an experienced climber, it’s also a good idea to train and climb mostly with the safer method. However, as you push your pocket strength, you should progressively expose your hands to the less safe method in your training. Slowly increase intensity over time to adapt the lumbricals to the high stresses of powerful pocket pulling. Pinch block and sloper training will also help build strength in these important hand muscles.