Why should we strength train the fingers?
Average times under tension for climbing are in the 4-7-second range. So it seems very logical to strength train the fingers to increase performance. At first glance, it makes sense to use a fingerboard. Hanging on our fingers with added weight should equal more available force on the climbing wall. Let’s see if it’s that simple.
Improving Muscle Recruitment
The title of this section speaks for itself. That is the primary and only thing we should expect to transfer to our sport. To generate more force actively, we need to send a large command from the brain to the finger flexors every rep. To do this, every rep needs to be high intensity and only last around 1-3-seconds in length, if that. Certainly not 4-7-seconds, the average time under tension on the climbing wall.
Strength : Improving Finger Flexor Coordination
This response happens before motor unit recruitment. It takes some time (weeks to months) for an athlete to be coordinated enough to increase motor unit recruitment. You can’t have one without the other. Even though adding load to the body on a fingerboard seems like an immediate force improvement, it isn’t. There’s quite a bit of coordination that happens at the start. For example, the forces using a 20mm edge (most commonly used) will not directly transfer to a 10mm edge. It is not the same skill. The mechanics of the hand aren’t identical in both positions.
Strength to Travel Greater Distances When Climbing
By increasing recruitment, the things that were once 90% are now 70%, etc. So as strength increases, everything becomes a little bit “easier.” This should allow us to travel farther at our limit. Or at least that’s how the story usually goes. Unfortunately, it’s not that simple. Training always has compromises. Strength training is low volume for a reason. To get the highest recruitment levels, we must keep fatigue low. That’s the opposite of endurance.
As coaches, we wouldn’t prescribe a capacity phase before a strength phase for this reason. For example, doing a lot of climbing or fingerboard volume makes the largest muscle fibers more aerobic (use oxygen better). This can be good for efficiency but isn’t optimal for peak force. It makes little sense to take an athlete off a performance phase and throw a bunch of volume at them. In fact that’s risky.
Loading the Connective Tissues for Tolerance/Health
Overloading the connective tissues has health benefits. For example, increasing stress regularly with strength training (material sciences definition) allows for more stiff tendons and ligaments. This stress is essential for building capacity or the ability to tolerate more climbing things. The thing we like about the fingerboard for newer climbers is the immediate loads it puts on the connective tissues of the fingers. Experienced climbers, however, don’t get the same response.