Fryer, SM, Giles, D, Garrido Palomino, I, de la O Puerta, A, and España-Romero, V. Hemodynamic and cardiorespiratory predictors of sport rock climbing performance. J Strength Cond Res 32(12): 3543-3550, 2018-Rock climbing performance has been suggested to involve a notable contribution from aerobic metabolism. Previously, it has been shown that forearm oxygenation kinetics can be used to distinguish ability groups and predict red-point sport climbing performance. Currently, it is not known if forearm oxygenation kinetics or a sport-specific assessment of cardiorespiratory fitness best predicts sport rock climbing performance. The aim of the study was to determine whether forearm oxidative capacity index, maximal deoxygenation (Δ score) during a treadwall VCombining Dot AboveO2peak test, treadwall VCombining Dot AboveO2peak, or running VCombining Dot AboveO2max best predicts self-reported sport climbing performance. Twenty-one male sport rock climbers completed a treadwall VCombining Dot AboveO2peak, running VCombining Dot AboveO2max, and an assessment of near-infrared spectroscopy-derived oxidative capacity index. Linear regression, adjusted for age and experience (years), revealed that forearm oxidative capacity index, treadwall maximal deoxygenation (Δ), and treadwall VCombining Dot AboveO2peak all significantly predicted self-reported red-point sport climbing ability (Adj R = -0.398, -0.255, and 0.374, respectively), whereas treadmill running VCombining Dot AboveO2max did not (Adj R = -0.052). Additionally, multiple regression suggested that the combined significant aerobic predictors accounted for 67% of the variance in red-point climbing ability. Findings suggest that training for sport rock climbing performance should look to incorporate modalities that focus on (a) improving local forearm aerobic capacity and (b) improving whole-body aerobic capacity using sport-specific apparatus, such as treadwalls.