S4, E5, Neuromuscular Re-Education of the Finger Flexors – Isabella Castro

If you would like to listen to the entire interview with Bella Castro, check out the podcast. If you want to watch the interview, click the YouTube link or any of the timestamps above. If you would like to read a concise recap of key interview topics and questions, check out the excerpt from the interview below.

Neuromuscular Re-Education of the Finger Flexors With Bella Castro, Doctor of Physical Therapy Student

Bella Castro noticed something on the wall that a lot of climbers will recognize: she would set up in a four-finger crimp, and her pinky would slide off. Every time. On every hold — even jugs. Rather than write it off as anatomy or a preference for the three-finger drag, Bella, a third-year Doctor of Physical Therapy student at the University of Southern California, took her physical therapy training and built a protocol around it. In this interview, she explains what neuromuscular re-education actually means, how to assess whether your fingers are doing what you think they’re doing, and how to retrain a grip position using exercises you can do at your desk, on the wall, and on the hangboard. She also shares the before-and-after footage from the case study she ran on herself.

“Neuromuscular re-education of the finger flexors” is a mouthful. What does it actually mean?

I think it might be the opposite of a clickbait title. It’s a little long, but it’s actually really interesting.

Neuromuscular re-education, simplified, is taking the aspect of the brain that can relearn things — neuroplasticity, the ability to create new connections — and using that capacity for learning to rebuild habits or learn new movement patterns. Applied to the finger flexors, that means retraining grip positions using habit training in the brain and making new connections.

So finger training isn’t all about max hangs?

Strength work can definitely be beneficial. The beauty of this, at least when I was studying it and writing the article, is that a lot of what we already do for strength training can be adapted into a different protocol so that it becomes neuromuscular re-education instead.

Where does a climber start? How do you assess this?

When I first started thinking about it, it was a self-assessment. I was on the wall and noticed that I would go into a crimp position with all four fingers on a hold, and no matter what, my pinky would slip right off and turn into a drag. It was constant. No matter how hard I tried to think about it, the pinky would pop back off. And getting that pinky back onto the hold is really hard — the force it takes, the energy and the time.

So the first step is assessing your own climbing. Watch a video of yourself and notice whether your grip position constantly changes even when you don’t want it to. Beyond that, are you constantly readjusting on the wall? Does it feel like your fingers don’t want to engage the way you want them to? And then the one climbers care a lot about: does your force output feel inconsistent, because you’re constantly changing your grip on the hold?

Once you notice that in yourself, we can move into a more clinical assessment and test different ranges of motion — is it muscular, is it joint position, or is it habit?

Once you’ve noticed it, how do you work out why it’s happening?

I don’t want to discredit anatomy. Sometimes the pinky is just really short and it’s difficult to get it onto a hold, and that could definitely be a component in why a certain grip feels more comfortable.

But start by assessing range of motion. If you look at your hand and go into a crimp position, and your pinky can get in line with the rest of your fingers, then theoretically you should be able to hold that grip position. The next question is whether you can control the pinky. I remember when I was testing everything on myself, for the life of me I could not bend my pinky on its own.

So muscular control is one component — can you isolate the finger — and range of motion is the other. Are you able to bend the finger at all and get full motion through it? That’s active motion. Passive matters too: with how much activation there is in certain climbers, they can be more susceptible to stiff muscles, which makes it harder to passively move the joint because everything is so tight.

How do you test finger proprioception?

Proprioception here means having the ability to feel the hold beneath your finger and know where your joint is in space. If I have no idea where my pinky is at any given moment, how can I expect it to land on the hold and stick there?

If you have a hangboard block, or even just any kind of edge, you can test it. Passively bend the finger — using your other hand, or have your climbing partner do it for you — so that you have something underneath it holding it in the desired position. You flex that finger passively into a certain amount of bend, and you feel how far it’s being flexed. Then you remove the support. That’s why the hangboard block is easier, because you can take it away cleanly. With your eyes closed, you try to reproduce the same position.

You can just put your finger on the table and move it from there. You can add weight, and that does provide more feedback into the finger because there’s more load on it — but doing it without anything pulling on the finger makes it more of a true proprioceptive test, with less feedback to rely on.

A physical therapist would use a goniometer. How can a climber measure the angle on their own?

Your climbing partner can measure it for you, or eyeball it. A physical therapist is the way to go, in my opinion. But you can also use the measurement app on an iPhone to measure angles. It might not be the most accurate, but it’s definitely something you can do on your own.

What’s the second test?

One of the easiest things you can do is an individual finger lift test. All you need is a flat surface. Place your hand on the table, then lift one finger at a time without letting the other fingers move.

Should that be done flat, or in a more challenged position?

It can be used both ways. If you’re a slab master, you might want to do this on a flat table. But if you’re consistently climbing overhang, where your hand has to clock back into extension in order to reach holds, it’s more beneficial in a plank position — with the muscles lengthened and the wrist extended.

Both are beneficial, and comparing the two can be a differentiating factor in working out what’s causing the tightness.

Say a climber fails these tests. What’s the framework for fixing it?

It goes back to the Rock Rehab Pyramid and its three core principles — mobility, strength, and movement.

First is mobility. As climbers, we can have tight muscles pretty much everywhere, especially in the forearms. So we start with stretching and mobilising the muscles that may be tight, because limited range of motion makes it difficult to unlock certain positions and movements. Typical forearm stretching works here.

The next parts are crucial, and they’re easy to implement into a warm-up or a training protocol, depending on what you like to do before a session.

What’s the first activation exercise?

This one was actually really hard when I first started doing it.

Your hand is laying flat on any surface, similar to the lift-off test. What you’re trying to do is bend your finger and slide it across the table, keeping the end part of your finger straight and only bending the middle joint. If your body isn’t used to that motion, it’s difficult. I remember I would be studying or doing something at home and I’d just be trying to get my finger to move the way I wanted it to, and it was really hard.

So any time you’re getting ready to warm up, or you’re at a desk doing work, you can start retraining that finger by bending it and sliding it across the table, trying to isolate it. You can do this for all of your digits — slide it and see how much control you can maintain. And if it’s easy on one hand, try the other. Sometimes it’s not.

A lot of neuromuscular re-education is just dependent on consistent movement and repetitions, over and over and over. The point of the first exercise is to move the finger through its range of motion and activate it actively, not passively — to unlock the movement for yourself before you take it to the wall.

How do you take it onto the wall?

That’s where we actually want to see the results. Sure, it could be a fun party trick to say look, I can move all my fingers independently — but it’s a lot more useful to be able to show it on the wall.

Something a lot of climbers already do is deadpoint practice. I like setting up a camera if the gym isn’t too busy, so I can watch myself in case I can’t catch it in my own body. Then it’s deadpoint repetitions, making sure you latch all of those fingers on the wall — going up, catching the hold in the position you want. In my case, not a three-finger drag, but a four-finger crimp, and maintaining it for a second.

From there it transfers to two deadpoints in a row, or moving across two holds. Deadpoint, move, next move, maintaining the desired grip position the whole way. That’s the progression — you start off the wall moving the finger through its range to build the habit, then you carry it onto the wall.

What about the hangboard?

This is also something you can do as part of a warm-up, and everyone either loves it or hates it.

These are assisted hangs, and it isn’t much to add to a hangboard protocol you’re already doing — or to implement if you don’t hangboard much. You bring your arm up into the desired grip and let about 50 to 75% of your body weight hang on the edge, so you aren’t lifting off. That lets your body start to feel what it’s like to keep all the fingers on, which goes back to proprioception. You’re getting the feedback of the edge on your fingers and starting to apply some weight, so you’re training strength in an assisted position.

You can do sustained holds using whichever on/off timing protocol you normally use, or you can work in an on-relax, on-relax pattern.

You ran a mini case study on yourself. What did the “before” footage look like?

It’s almost comical seeing how my pinky just slides off. There’s a part of the video where you can watch me struggling to get that pinky back on. That was on the Moon Board and the Kilter Board, and it was happening on every hold — even on a jug, my pinky just falls off. It was both hands, dominant and non-dominant.

For the longest time I told myself I was just more comfortable in a three-finger drag, which can genuinely be true for a lot of people. It is more comfortable in terms of having that open hand and using a little less force. But sometimes you want the force of all four fingers and your weight distributed across all four. The three-finger drag is a great hand position — I’m not in any way saying it’s bad — but it’s nice to be able to control when you use it and when you don’t.

And the after?

I was a little sad, because while I was doing the protocol on myself they changed the year of the Moon Board set, so I couldn’t do the exact same climb to show. But I did another climb where you can see my pinky stays on, which is super exciting.

Beyond the footage, there’s the confidence in my climbing. There wasn’t as much repositioning to do. Everything felt a little stronger and more controlled. I still often use my three-finger drag, but now it’s not my pinky pulling off and giving me an unexpected three-finger drag — it’s a three-finger drag when I want it to be.

I also had a friend do it who was experiencing the same problem. They never sent me any of their videos, but they said they’re doing better, which is great to hear.

Does this only apply to the pinky?

Not at all. Most of what we do as climbers is learned movement. So if you can learn what’s stopping you from consistently performing the movement you want, you can learn how to retrain it. The brain is just really cool that way — you can relearn movement and make things more optimal for you.

The three-finger drag is one example, but this works for any grip position. Pinches are another one: it could be about settling the thumb into a certain position. There are so many different ways to take these principles and implement them, and I think it’s great that it’s broad like that.

Any closing thoughts?

Start by noticing the small climbing habits in yourself, whether that’s feeling something on the wall or seeing it consistently on video. There isn’t much research out there on this specifically — most of what I drew on comes from work done in other joint regions — so I’d love to see more people looking into it.

And it isn’t only about performance. If you know what your body is doing and you know how to control it, that may reduce your risk of injury, because you won’t have as many unexpected pinky drops like I did. Learning that and being able to control it can help with future instances and decrease the probability of injury.

Where can we find more information?

To connect, you can reach Bella via Instagram @bella.castro.