How do pulleys get injured? New study shows that eccentric loading is the culprit.

Let’s talk about fingers — shocking, I know. We never talk about our fingers… or stare at them incessantly… or obsess about every aspect of them.

You rely on them for every climb, but how much do you really know about keeping them healthy? If your idea of finger care is slapping on some tape and praying for the best, it’s time for a wake-up call.

Today, we’re diving into a game-changing study by Schoffl and his crew of climbing nerds, who looked at how different types of crimping affect your precious finger pulleys. Spoiler: not all crimping is created equal, and if you’re not paying attention, you could be setting yourself up for an injury that’ll leave you swiping on Tinder instead of boulders.

Let’s break it down. So you can climb smarter — not sidelined.

Crimping 101: Know Your Moves

Before we geek out on the study, let’s get our terminology straight. Because if you’re going to nerd out about finger science, you might as well do it right.

• Isometric Crimping:
  Holding the crimp without changing your joint position. Basically, this is most of the crimping you do (when you’re not falling!).

• Concentric Crimping:
  Curling your fingers more while crimping. Think “bearing down” mid-crux when you’re giving it everything you’ve got.

• Eccentric Crimping:
  Crimping while your fingers slowly extend or open. This happens when your foot pops, or when you’re so pumped that you’re sliding off the hold.

Got it? Cool. Now let’s see what Schoffl’s study says about how these movements stress your finger pulleys.

Here’s an elaborated version of the paragraphs, adding more context, depth, and actionable insights:

The Study: What Happens When You Pop a Foot While Climbing

Schoffl’s research didn’t just skim the surface — it took a deep dive into how your fingers handle the demands of climbing. The study examined 30 climbers with a mix of experience levels, from newbies who still chalk up too much to seasoned crushers who send 5.13s for breakfast. The goal? To analyze how two types of crimping—concentric (bearing down harder) and eccentric (when your foot pops but you still hold on)—impact the finger pulley system. Spoiler alert: your fingers take a beating no matter what, but some scenarios are significantly worse.

Eccentric Crimping: The Villain of Finger Pulleys

The big takeaway from the study is that eccentric crimping places way more stress on your finger pulleys than concentric crimping. Why? Because eccentric loading involves your muscles contracting while lengthening under tension. In layman’s terms, this happens when you’re holding on to a crimp, but your fingers are being pulled open—like when your foot pops off a foothold mid-move, or when you’re slowly sliding off a hold because you’re too pumped to hold on anymore.

That instinctive reaction to bear down harder? Yeah, that’s the moment your pulleys are screaming, “We can’t take this much longer!” The force can spike unexpectedly, and unlike concentric loading, where you’re pulling in a controlled way, eccentric crimping adds an element of chaos and unpredictability to the mix. It’s a perfect storm for injury if your pulleys aren’t prepared to handle the load.

Experience Matters (but It’s Not a Free Pass)

Here’s where things get interesting: the study also revealed that experienced climbers have a higher tolerance for stress on their finger pulleys compared to beginners. Why? Years of consistent climbing and training lead to adaptations in the pulley system, making it more resilient to wear and tear. Think of it like building calluses on your skin or strengthening your tendons over time—your body gets tougher the more you expose it to controlled, progressive stress.

There are many ways you can injure your pulleys, and just because there is huge load on the pulleys, it doesn’t mean you’re going to get injured. But don’t get cocky. Even if you’ve been climbing for years, your fingers aren’t invincible. Eccentric crimping still puts greater stress on your pulleys, so keep those feet on the wall.

What This Means for Your Training

So, what does all this nerdy finger science mean for us mere mortals pulling on plastic or outside? Let’s break it down into actionable advice you can take to the gym or crag.

1. Add Eccentric Crimping to Your Training
   Most climbers focus on concentric strength, but neglecting eccentric work is like skipping leg day. Controlled eccentric exercises, like lowering slowly from a hangboard or downclimbing on a campus board, can help you build both strength and resilience. Think of it as armor for your finger pulleys.

2. Progress Gradually (Seriously, Don’t Skip This)
   If you’re new to eccentric training, start slow. Your pulleys need time to adapt. Begin with lighter loads or shorter durations, and gradually increase intensity. This isn’t a race—it’s about keeping your fingers intact for the long haul.

3. Respect Experience (but Don’t Be Cocky)
   Experienced climbers in the study could handle more stress on their pulleys. That’s great news if you’ve been climbing consistently for years, but it’s not a free pass to overdo it. Even pros can get injured if they push too hard without recovery.

4. Listen to Your Body (and Don’t Ignore Pain)
   Pain isn’t weakness leaving the body; it’s your body telling you to back the hell off. If your fingers hurt during or after a climb, take it seriously. Persistent pain? See a PT (hi, that’s me!) before you make things worse. Trust me, it’s better to address a tweak early than to sit out for months with a full-blown injury.

Injury Prevention = More Sends 

Look, I get it. Nobody wants to sit on the crash pad while their friends are crushing it or be relegated to being the designated spotter for the group. But if you ignore the science and push through pain, you’re gambling with your climbing future. Incorporating eccentric training, progressing slowly, and listening to your body aren’t just smart—they’re how you stay on the wall longer and stronger.

So, here’s the deal: Treat your fingers like gold. Warm up, train smart, and respect the fact that your pulley system isn’t invincible. And if you do find yourself nursing a tweaked finger, don’t just slap on some tape and hope for the best. Book a session with someone who gets climbers (yep, still me). Your fingers will thank you—and so will your climbing buddies when you’re back on the wall, crushing it. 

Ready to Climb Smarter?

If finger pain is keeping you off the wall, schedule a session with one of the physical therapists at Rock Rehab in Santa Fe, New Mexico. Whether you need a recovery plan or want to prevent injuries before they happen, we’re here to help. Let’s keep you climbing strong.