Crimps and Active Tension on Fingers
athletes rely a lot on passive structures, which lead to implications for wrist pain.
When we talk about 'active positions' in climbing, we're referring to grips like the half and full crimp.
These positions, unlike the open-hand position, require the MCP (knuckles) and PIP joints to flex for better leverage.
The size of the edge being gripped determines the amount of flexion needed.
In this scenario, the hand creates a C-shape like the hooks used in aid climbing.
The goal is to create a unique-to-you (multiple sizes and widths) lever arm, allowing the center of mass to get directly below the fingers.
To get in this position, the muscles on the back of the forearm (extensors) must contract at a relatively high but constant force to optimize this leverage.
Wrist extension pre-stretches the finger flexors and bends the MCP joints first, allowing for subsequent finger flexion.
Compared to the sloper or open position, the half and full crimp grips add more muscle activity.
These positions add active tension or stability across the wrist joint.
In this scenario, the reliance on passive structures (joint capsules, ligaments) is reduced.
For my clients with wrist pain, defaulting to more active positions is quite helpful during rehab.
It helps "close" the joint by putting force on the tendons that cross it. In addition to strength training off the wall, the most important thing to consider is the muscular fatigue endured during the climbing session.
Once the muscles tire, the ability to contact/coordinate quickly across the joint reduces, exposing the passive structures to more stress.
A big takeaway for climbers with wrist pain is that there's a lot of healthy, uninjured tissue that helps stabilize the wrist. Strength training, climbing with modifications, and finger training aren't "off limits" necessarily.
Modifications to your training, that is, reductions in climbing volume (not always intensity), new types of loading (strength training), and better wellness practices (sleep, diet, mental health) likely are. I'd be really careful with slopers, though!