Author(s): SURAN, T., LENDVORSKY, L., TOLKUNOV, T., SPITKOVA, K., DUBRAVSKY, R., KOVAC, M., PELIKANOVA, J., Institution: NARODNE SPORTOVE CENTRUM, Country: SLOVAKIA, Abstract-ID: 2155

INTRODUCTION:
Near-infrared spectroscopy (NIRS) enables continuous non-invasive monitoring of muscle oxygen saturation (SmO2) during high-intensity exercise. The SmO2 deoxygenation slope (%·s⁻1) reflects the rate of local oxygen extraction and may indicate local metabolic demand and neuromuscular activation. Evidence linking NIRS kinetics with neuromuscular performance in ice hockey remains limited. To examine associations between SmO2 deoxygenation slope during a maximal cycling task and markers of explosive performance and hip isometric strength in elite junior ice hockey players.
METHODS:
Ten male elite junior players (age 18.3 ± 1.3 y; height 180.5 ± 4.9 cm; body mass 80.6 ± 6.8 kg) completed a 30-s Wingate test on a cycle ergometer. Bilateral vastus lateralis SmO2 was recorded using wearable NIRS sensors. A composite deoxygenation slope was calculated as the mean of left and right limb z-scores. Explosive performance was assessed using squat jump (SJ), countermovement jump (CMJ), and broad jump on force platforms. Maximal isometric hip adductor and abductor strength was measured using a fixed dynamometer in absolute and relative units. Pearson correlations were used to examine associations.
RESULTS:
Peak and mean Wingate power showed weak associations with SmO2 deoxygenation slope (highest r = 0.36). Large positive correlations were observed between deoxygenation slope and neuromuscular performance: SJ (r = 0.71, p = 0.021), CMJ (r = 0.74, p = 0.016), relative adductor strength (r = 0.83, p = 0.003), and relative abductor strength (r = 0.71, p = 0.022).
CONCLUSION:
A steeper SmO2 deoxygenation slope was associated with greater explosive and isometric hip strength, suggesting that faster local oxygen extraction may reflect greater neuromuscular performance capacity. NIRS-derived deoxygenation kinetics may represent a practical non-invasive marker of lower-limb performance in elite junior ice hockey players.