Dataset Information

Measuring critical force in sport climbers: a validation study of the 4 min all-out test on finger flexors.

ABSTRACT:

Purpose

The critical force (CF) concept, differentiating steady and non-steady state conditions, extends the critical power paradigm for sport climbing. This study aimed to validate CF for finger flexors derived from the 4 min all-out test as a boundary for the highest sustainable work intensity in sport climbers.

Methods

Twelve participants underwent multiple laboratory visits. Initially, they performed the 4 min intermittent contraction all-out test for CF determination. Subsequent verification visits involved finger-flexor contractions at various intensities, including CF, CF -2 kg, CF -4 kg, and CF -6 kg, lasting for 720 s or until failure, while monitoring muscle-oxygen dynamics of forearm muscles.

Results

CF, determined from the mean force of last three contractions, was measured at 20.1 ± 5.7 kg, while the end-force at 16.8 ± 5.2 kg. In the verification trials, the mean time to failure at CF was 440 ± 140 s, with only one participant completing the 720 s task. When the load was continuously lowered (-2 kg, -4 kg, and -6 kg), a greater number of participants (38%, 69%, and 92%, respectively) successfully completed the 720 s task. Changes of muscle-oxygen dynamics showed a high variability and could not clearly distinguish between exhaustive and non-exhaustive trials.

Conclusions

CF, based on the mean force of the last three contractions, failed to reliably predict the highest sustainable work rate. In contrast, determining CF as the end-force of the last three contractions exhibited a stronger link to sustainable work. Caution is advised in interpreting forearm muscle-oxygen dynamics, lacking sensitivity for nuanced metabolic responses during climbing-related tasks.

SUBMITTER: Jiri B

PROVIDER: S-EPMC11365833 | biostudies-literature | 2024 Sep

REPOSITORIES: biostudies-literature

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Publications

Measuring critical force in sport climbers: a validation study of the 4 min all-out test on finger flexors.

Baláš Jiří J Gajdošík Jan J Javorský Tomáš T Berta Patrik P Feldmann Andri A

European journal of applied physiology 20240426 9

<h4>Purpose</h4>The critical force (CF) concept, differentiating steady and non-steady state conditions, extends the critical power paradigm for sport climbing. This study aimed to validate CF for finger flexors derived from the 4 min all-out test as a boundary for the highest sustainable work intensity in sport climbers.<h4>Methods</h4>Twelve participants underwent multiple laboratory visits. Initially, they performed the 4 min intermittent contraction all-out test for CF determination. Subsequ ...[more]

PMID: 38668851

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Dataset Information

Measuring critical force in sport climbers: a validation study of the 4 min all-out test on finger flexors.

Purpose

Methods

Results

Conclusions

Publications

Measuring critical force in sport climbers: a validation study of the 4 min all-out test on finger flexors.

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