🧬 biology

Upper limb function, speed climbing performance and musculoskeletal discomfort in professional speed climbers: an exploratory cross-sectional study

This exploratory cross-sectional study of 26 professional speed climbers found that greater relative pulling strength is moderately associated with faster 15-meter completion times and that while upper-limb musculoskeletal discomfort is prevalent, performance capacity and symptom burden should be assessed as complementary dimensions.

Original authors: Peng Liu, Caihua Fang, Zeyong Xu, Binghong Gao

Published 2026-11-13

📖 5 min read🧠 Deep dive

CC BY 4.0

Original authors: Peng Liu, Caihua Fang, Zeyong Xu, Binghong Gao

Original paper licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). ⚕️ This is an AI-generated explanation of a preprint that has not been peer-reviewed. It is not medical advice. Do not make health decisions based on this content. Read full disclaimer

Speed climbing is a race against the clock on a vertical wall, where athletes must scale a standardized fifteen-meter route faster than anyone else. In this high-stakes environment, the upper body does the heavy lifting. While the legs provide the initial push, the arms and shoulders must grip, pull, and support the climber's entire weight as they surge upward. Because the muscles of the fingers, arms, and shoulders are working so hard, they are also the most likely to develop pain or injury. Coaches and scientists have long wondered if there is a specific way to measure an athlete's upper-body strength that predicts who will be the fastest, and whether the same tests can reveal who is carrying a hidden burden of pain. Understanding the link between raw power, movement efficiency, and physical discomfort is crucial for keeping elite climbers healthy and competitive.

A recent study set out to explore these connections by examining a group of twenty-six professional speed climbers from a provincial team in China. The researchers wanted to see if specific strength tests could explain why some athletes were faster than others, and if those same tests could identify athletes suffering from recent aches and pains. They focused on three main areas: how much extra weight a climber could pull up with their body, how strong their shoulders were in specific positions, and how well they could balance and reach with their arms while hanging. They also asked the athletes to report any discomfort they had felt in their shoulders, elbows, wrists, or fingers over the last month, and how much that pain affected their training and racing.

The most direct measure of strength turned out to be the weighted pull-up. In this test, athletes hung from a bar and pulled their bodies up while wearing a belt with added weight. The researchers calculated how much extra weight each person could lift relative to their own body size. They found a clear pattern: the athletes who could pull up more extra weight relative to their body mass tended to have faster personal best times on the fifteen-meter course. This relationship showed a moderate inverse association even when the researchers accounted for the fact that men and women generally have different body sizes and strength levels, although the association did not meet the strict threshold for statistical significance after correcting for multiple comparisons. While the statistical certainty was not absolute due to the small number of participants and the correction applied, the trend suggests that the ability to pull one's own body weight plus extra load is a relevant factor for speed.

The study also looked at shoulder strength in three specific positions, known as I, Y, and T, which test the muscles around the shoulder blade in different angles. The results here were consistent with the pull-up findings but slightly less clear. Athletes who were faster generally showed stronger shoulder muscles in these positions, particularly on the side of the body that was lower during the test. However, the researchers noted that these shoulder strength numbers did not perfectly separate the fastest climbers from the slower ones. Some slower climbers had shoulder strength scores similar to the fastest ones, suggesting that while shoulder power matters, it is not the only factor determining speed. The study also measured grip strength, but found that simply squeezing a handheld device did not predict race times as well as the full-body pull-up test did, likely because the way a climber holds a rock hold is more complex than a simple squeeze.

Beyond speed, the researchers investigated the athletes' physical well-being. More than sixty percent of the climbers reported feeling some discomfort in their upper limbs during the month before the study. The most common trouble spots were the shoulders and the fingers, with each area affecting about one-third of the group. Interestingly, the study did not find a simple link between having pain and being weaker. For instance, athletes who reported finger pain actually showed slightly better scores on some of the shoulder balance and strength tests compared to those without pain. The researchers suggested this might happen because the athletes who are training the hardest and performing the best are also the ones putting the most stress on their bodies, leading to more reported aches. They also looked at whether having one side of the body stronger than the other was related to pain, but found no consistent evidence to support that idea.

The authors concluded that while pulling strength is a strong indicator of speed, the relationship between strength, performance, and pain is complex. The data suggests that coaches should look at an athlete's pulling capacity and shoulder strength together to build a profile of their potential, but they should not expect these numbers to perfectly predict who will get hurt. The study highlights that speed climbing performance and physical discomfort are two different dimensions that need to be monitored separately. The researchers emphasized that their findings are a starting point, offering a snapshot of a specific group of athletes. They recommend that future studies follow climbers over time to see if changes in strength or the development of pain can be predicted, helping to keep these athletes at the top of their game for longer.

Technical Summary: Upper Limb Function, Speed Climbing Performance, and Musculoskeletal Discomfort in Professional Speed Climbers

Problem Statement
Speed climbing requires athletes to ascend a standardized 15-meter route as rapidly as possible, a task heavily dependent on upper-limb pulling capacity, finger flexor strength, and shoulder positioning. While previous research has established links between upper-body strength and performance in climbing, there is a need to distinguish specific functional capacities associated with speed climbing from general musculoskeletal function and recent symptom burden. Existing literature often lacks a multidimensional assessment that simultaneously evaluates competitive performance, specific upper-limb strength profiles (including position-specific forces), and recent musculoskeletal discomfort within a professional cohort. This study addresses the gap in understanding how relative pulling strength and shoulder-position-specific force relate to competitive performance and how these functional measures correlate with recent upper-limb discomfort in provincial-level professional speed climbers.

Methodology
This exploratory cross-sectional study enrolled 26 provincial-level professional speed climbers (17 men, 9 women; mean age 17.85 ± 3.34 years). The study adhered to STROBE guidelines and received ethical approval from the Hunan Institute of Sports Science.

Performance Metric: The primary outcome was the personal-best 15-m completion time from official competitions within the preceding year.
Functional Assessments:
- Weighted Pull-ups: Measured as additional load relative to body mass (kg/kg).
- I/Y/T Isometric Strength: Measured using digital dynamometry in three shoulder positions (I, Y, T) and normalized to body weight (BW).
- Grip Strength: Measured via hand dynamometer, normalized to body mass.
- Upper Quarter Y-Balance Test (UQYBT): Assessed closed-chain upper-quarter performance.
Symptom Assessment: The Oslo Sports Trauma Research Centre Overuse Injury Questionnaire (OSTRC-O), adapted for speed climbing, was used to assess upper-limb discomfort and its impact on participation, training, and performance over the past four weeks.
Statistical Analysis: Given the small sample size and skewed distributions, non-parametric methods were employed. Spearman correlations, sex-adjusted rank correlations (using residuals from sex regression), permutation tests (20,000 permutations), and bootstrap confidence intervals (10,000 samples) were calculated. The Benjamini–Hochberg procedure was applied to control for false discovery rates (FDR) across multiple hypothesis tests. Post-hoc sex-specific performance tertiles were used to contextualize strength distributions.

Key Results

Performance Correlates: Relative weighted pull-up load showed a strong inverse correlation with 15-m completion time (Spearman's $\rho = -0.66$ ; $q = 0.005$ ). After adjusting for sex, the association remained moderate ( $\rho = -0.55$ ; permutation $P = 0.008$ ) but did not survive multiplicity correction ( $q = 0.077$ ).
Secondary Strength Measures: I/Y/T mean and lower-side relative strength showed directionally consistent secondary associations with performance ( $\rho \approx -0.50$ ), though these also failed to meet the corrected significance threshold ( $q = 0.077$ ). Grip strength relative to body mass showed a weaker association with performance compared to pull-up load.
Discomfort Prevalence: 17 athletes (65.4%) reported upper-limb discomfort in the preceding four weeks. The most common sites were the shoulder/scapular region and fingers (34.6% each).
Symptom-Function Relationships: No symptom-related comparisons survived multiplicity correction. Athletes with finger discomfort exhibited higher UQYBT scores and lower I/Y/T asymmetry compared to those without, but these differences were only nominally significant ( $P = 0.020–0.046$ ) and lost significance after FDR correction ( $q = 0.369$ ). No clear associations were found between shoulder/scapular discomfort and functional measures.
Asymmetry and Discrepancy: Bilateral asymmetry measures showed no significant association with OSTRC scores. A nominal positive correlation was found between the OSTRC score and the I/Y/T mean relative-strength discrepancy index ( $\rho = 0.39$ ; $P = 0.049$ ), but this did not survive correction.

Key Contributions

Cohort-Specific Profiling: The study provides an initial descriptive profile of upper-limb function in professional speed climbers, linking relative weighted pull-up load and I/Y/T strength to competitive performance.
Sex-Specific Reference Data: It establishes sex-specific distributions for additional pull-up load and I/Y/T strength across performance tertiles. For example, in the faster male tertile, the median additional load was 1.024 times body mass, compared to 0.818 in the faster female tertile.
Multidimensional Assessment Framework: The research integrates competitive performance, specific strength metrics, and symptom burden (via OSTRC) into a single analysis, highlighting the distinction between performance capacity and recent symptom load.
Methodological Rigor: The study employs robust statistical techniques, including permutation tests, bootstrap intervals, and FDR correction, to provide a transparent assessment of association strength and precision in a small sample.

Significance and Claims
The paper claims that relative pulling capacity (weighted pull-ups) and position-specific I/Y/T force provide a descriptive profile of faster athletes within this specific cohort. The authors emphasize that while relative weighted pull-up load is the strongest candidate performance correlate, the association is modest after sex adjustment and multiplicity correction.

The study concludes that performance capacity and recent symptom burden should be assessed as complementary, distinct dimensions rather than directly predictive of one another in this cross-sectional context. The sex-specific distributions and performance bands offer an initial reference for coaches and researchers to contextualize repeated strength assessments against an athlete's own performance and training exposure. The authors explicitly state that the findings do not support the use of these measures for symptom classification or injury prediction in their current form, noting that the lack of significant associations after correction suggests a need for larger, longitudinal studies to distinguish stable individual differences from short-term risk signals. The study serves as a foundational step for future prospective research involving repeated measurements and more granular symptom tracking.

Technical Summary: Upper Limb Function, Speed Climbing Performance, and Musculoskeletal Discomfort in Professional Speed Climbers

More like this