Contact Strength vs. Finger Strength: Understanding the Differences for Climbing Performance

Let’s dive into one of the most critical components of climbing: contact strength.

While finger strength often gets the spotlight, the ability to generate quick, high force through your hands, or contact strength, is what can make the difference in your climbing.

Recap: Strength Adaptations for Climbing

In recent discussions, we’ve explored the specific adaptations you can expect from a well-structured finger strength program. This includes increased muscular recruitment, hypertrophy, and enhanced stiffness of connective tissues. These adaptations are essential because they allow climbers to have more productive, quality training sessions, leading to more significant gains over time. Remember, it's not about producing massive force while on the wall but improving overall efficiency.

The Role of Strength in Power Development

To build contact strength, we must first recognize that strength is the foundation for power. As Yuri Verkoshansky, one of the pioneers of sports science, noted in the 1960s: strength precedes power. This still holds true today. To become more powerful, particularly in your hands, you need to build a foundation of strength first.

Why is this? Strength training increases the stiffness of connective tissues, allowing tendons to contract at the same speed as muscles. Additionally, strength training helps you tap into high-threshold motor units, which are composed primarily of fast-twitch muscle fibers. These fibers are essential for producing rapid, explosive movements, like grabbing a hold during a dynamic move.

Understanding Fast-Twitch vs. Slow-Twitch Muscle Fibers

To appreciate fast-twitch fibers, it’s useful to compare them with slow-twitch fibers. Slow-twitch fibers are more fatigue-resistant and are utilized during lower-intensity, longer-duration climbing. In contrast, fast-twitch fibers are activated during high-intensity, explosive movements. These fibers fatigue more quickly, which is why your climbing sessions must be shorter when training at higher intensities.

The Hand and Forearm: A Unique Mix of Muscle Fibers

Recent research has shed light on the muscle composition of the hand and forearm. Interestingly, the intrinsic muscles of the hand, such as the lumbricals and interossei, have more fast-twitch fibers than the extrinsic finger flexors and extensors. These smaller muscles, often overlooked, play a significant role in contact strength.

This research suggests that these muscles are critical in the initial stages of grasping, particularly flexing the metacarpophalangeal (MCP) joints before the fingers follow. This means that focusing on grips that activate these muscles, such as the talon grip, can be beneficial for climbers.

Training for Power: Slow Movements Won’t Cut It

One of the best ways to increase recruitment of high-threshold motor units is through progressive overload with stable strength movements. However, strength training exercises alone won’t guarantee better climbing performance. Why? Because the movements used in traditional strength training are often too slow to translate directly into improved contact strength.

When you’re grabbing a difficult hold, you don’t have the luxury of a full second to generate maximum force, as you might on a fingerboard. Instead, you need to develop strength at a much faster rate. This is where the concept of impulse comes into play.

The Importance of Velocity in Power Training

In traditional sports, we can see a vast difference in the speed of strength movements and athletic movements. For example, the velocity of a max-effort back squat is significantly slower than that of a vertical jump. Similarly, in climbing, while hangboard training can build force, it doesn’t replicate the rapid force application needed during dynamic moves on the wall.

To improve contact strength, you must train to produce force quickly. That’s why limit-level bouldering moves, where speed and coordination are prioritized, are so valuable. But remember, power training should be done in lower volumes, as fast-twitch fibers fatigue quickly. When these fibers become fatigued, your coordination suffers, increasing the risk of injury and limiting performance gains.

Climbing Research and Contact Strength

While there’s still limited research on the rate of force development needed to grab various holds on the wall, a few studies provide valuable insights. For instance, elite climbers can produce up to 108 pounds of force within 200 milliseconds on a 23mm edge. This rapid force production is essential for high-performance climbing.

Comparatively, boulderers tend to produce slightly more force in these tests than sport climbers, suggesting that different disciplines may require varied training approaches.

Next Steps for Contact Strength Training

In another post, we’ll explore non-climbing methods to improve power and contact strength. While limit bouldering is a great tool, off-the-wall exercises like finger pull-ups and using devices like the Tindeq Progressor can also contribute to these adaptations. However, these movements need to be lighter and faster to effectively enhance contact strength.