What’s the Best Way to Test Finger Strength for Climbers?

What’s the Best Way to Test Finger Strength for Climbers?

Finger strength is a cornerstone of climbing performance, and there’s no shortage of protocols to assess it. The problem? Few of them are standardized, and even fewer report both reliability and validity in a controlled setting. This study, published in the Journal of Sports Sciences, takes a stab at answering a key question: Which body position offers the most reliable and performance-relevant measure of climbing-specific finger strength?

What They Did

Twenty-six intermediate to elite-level climbers were recruited and tested in four distinct positions using an isometric pull-down on a 23-mm edge:

  1. Seated, bent arms (Sit - 90)

  2. Seated, straight arms (Sit - 180)

  3. Standing, bent arms (Stand - 90)

  4. Standing, straight arms (Stand - 180)

Each climber completed three maximal efforts per position on two separate days, spaced 48–96 hours apart. Both absolute (raw force) and relative (N/kg body mass) finger strength were analyzed. Researchers looked at within-session and between-session reliability and how well these strength measures correlated with climbing performance.

Key Findings

1. All Test Positions Were Reliable

  • All positions showed excellent test-retest reliability (ICC > 0.95).

  • Within-session variation was low (CV < 3.5% across the board).

  • The seated positions, particularly Sit90, showed slightly better consistency.

2. Bent Arms Were Slightly More Reliable

  • Both seated and standing positions with bent elbows had higher ICCs and lower error margins.

  • Likely due to mechanical stability: fewer degrees of freedom and less postural sway.

3. Relative Strength Was More Predictive Than Absolute Strength

  • Relative force values (N/kg) correlated more strongly with climbing performance, especially in sport climbing.

  • For bouldering, absolute strength was already highly predictive, and adjusting for body mass only marginally improved associations.

4. Seated Bent-Arm Position Was Best Overall

  • The Sit90 position had the strongest correlations with both bouldering (r = 0.73) and sport climbing (r = 0.64).

  • Standing positions trailed slightly, possibly due to greater movement variability.

5. Averaging Three Trials vs. Best Single Attempt? Both Work.

  • The mean of three trials showed marginally better reliability.

  • But using the best single attempt yielded nearly identical outcomes and may boost effort in practical settings.

Physiology Perspective

Testing with the elbow at 90° likely recruits more proximal stabilization—think of it as engaging more of the shoulder complex to anchor the finger pull. This decreases “noise” from trunk sway or scapular movement. Fully extended elbows, while arguably more climbing-specific, offer less stability and may allow subtle shifts in posture that affect force output.

The fact that relative strength was a better predictor aligns with long-standing principles in climbing and gymnastics: strength-to-weight ratio is king. In sports where athletes move their body against gravity, scaling strength to body mass captures the functional relevance of raw force better than absolute values.

Practical Implications

For practitioners, especially those testing finger strength in clinical or performance settings:

  • Use a seated position with bent elbows if possible.

  • Choose between averaging three trials or the best attempt depending on context—both are reliable.

  • If you're tracking performance over time, stick with one method for consistency.

This test setup is valid and reliable, and it’s also implementable without expensive lab equipment. Force sensors, a standardized edge, and a consistent rig are all required.

Citation:
Stien, N., Andersen, V., Langer, K., & Saeterbakken, A. H. (2025). Assessing climbing-specific strength: The impact of body position and elbow flexion on reliability and predictive validity. Journal of Sports Sciences. https://doi.org/10.1080/02640414.2025.2477863




Tyler Nelson