PURPOSE: Sport climbing requires high-intensity finger flexor contractions, along with a substantial whole-body systemic oxygen uptake ([Formula: see text]O2) contribution. Although fatigue is often localised to the finger flexors, the role of systemic ̇[Formula: see text]O2 and local aerobic mechanisms in climbing performance remains unclear. As such, the primary purpose of this study was to determine systemic and local muscle oxygen responses during both isolated finger flexion and incremental exhaustive whole-body climbing tests. The secondary aim was to determine the relationship of isolated and whole-body climbing endurance tests to climbing ability. METHODS: Twenty-two male sport climbers completed a series of isometric sustained and intermittent forearm flexor contractions, and an exhaustive climbing test with progressive steepening of the wall angle on a motorised climbing ergometer. Systemic [Formula: see text]O2 and flexor digitorum profundus oxygen saturation (StO2) were recorded using portable metabolic analyser and near-infra red spectroscopy, respectively. RESULTS: Muscle oxygenation breakpoint (MOB) was identifiable during an incremental exhaustive climbing test with progressive increases in angle (82 ± 8% and 88 ± 8% [Formula: see text]O2 and heart rate climbing peak). The peak angle from whole-body treadwall test and impulse from isolated hangboard endurance tests were interrelated (R2 = 0.58-0.64). Peak climbing angle together with mean [Formula: see text]O2 and StO2 from submaximal climbing explained 83% of variance in self-reported climbing ability. CONCLUSIONS: Both systemic and muscle oxygen kinetics determine climbing-specific endurance. Exhaustive climbing and isolated finger flexion endurance tests are interrelated and suitable to assess climbing-specific endurance. An exhaustive climbing test with progressive wall angle allows determination of the MOB.

• Klíčová slova
• Intermittent exercise, Isometric contraction, Muscle oxygen, NIRS, Threshold,
• MeSH
• blízká infračervená spektroskopie MeSH
• dospělí MeSH
• fyzická vytrvalost fyziologie   MeSH
• horolezectví fyziologie   MeSH
• kosterní svaly fyziologie   MeSH
• lidé MeSH
• prsty ruky fyziologie   MeSH
• síla ruky fyziologie   MeSH
• spotřeba kyslíku fyziologie   MeSH
• svalová kontrakce fyziologie   MeSH
• svalová únava fyziologie   MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Purpose: Sport climbing is a technical, self-paced sport, and the workload is highly variable and mainly localized to the forearm flexors. It has not proved effective to control intensity using measures typical of other sports, such as gas exchange thresholds, heart rate, or blood lactate. Therefore, the purposes of the study were to (1) determine the possibility of applying the mathematical model of critical power to the estimation of a critical angle (CA) as a measure of maximal metabolic steady state in climbing and (2) to compare this intensity with the muscle oxygenation breakpoint (MOB) determined during an exhaustive climbing task. Materials and Methods: Twenty-seven sport climbers undertook three to five exhaustive ascents on a motorized treadwall at differing angles to estimate CA, and one exhaustive climbing test with a progressive increase in angle to determine MOB, assessed using near-infrared spectroscopy (NIRS). Results: Model fit for estimated CA was very high (R 2 = 0.99; SEE = 1.1°). The mean peak angle during incremental test was -17 ± 5°, and CA from exhaustive trials was found at -2.5 ± 3.8°. Nine climbers performing the ascent 2° under CA were able to sustain the task for 20 min with perceived exertion at 12.1 ± 1.9 (RPE). However, climbing 2° above CA led to task failure after 15.9 ± 3.0 min with RPE = 16.4 ± 1.9. When MOB was plotted against estimated CA, good agreement was stated (ICC = 0.80, SEM = 1.5°). Conclusion: Climbers, coaches, and researchers may use a predefined route with three to five different wall angles to estimate CA as an analog of critical power to determine a maximal metabolic steady state in climbing. Moreover, a climbing test with progressive increases in wall angle using MOB also appears to provide a valid estimate of CA.

• Klíčová slova
• critical power, finger flexors, muscle oxygenation, near infrared spectroscopy, oxygen kinetics, sport climbing,
• Publikační typ
• časopisecké články MeSH