Oxygen Uptake and Muscle Deoxygenation Kinetics During Skating: Comparison Between Slide-Board and Treadmill Skating.

PURPOSE: To compare the oxygen-uptake ([Formula: see text]) kinetics during skating on a treadmill and skating on a slide board and to discuss potential mechanisms that might control the [Formula: see text] kinetics responses during skating.
METHODS: Breath-by-breath pulmonary [Formula: see text] and near-infrared spectroscopy-derived muscle deoxygenated hemoglobin and myoglobin ([HHbMb]) were monitored continuously in 12 well-trained, young, long-track speed skaters. On-transient [Formula: see text] and [HHbMb] responses to skating on a treadmill and skating on a slide board at 80% of the estimated gas exchange threshold were fitted as monoexponential function. The signals were time-aligned, and the individual [HHbMb]-to-[Formula: see text] ratio was calculated as the average value from 20 to 120 s after exercise starts.
RESULTS: The time constants for the adjustment of phase II [Formula: see text] (τ [Formula: see text]) and [HHbMb] (τ [HHbMb]) were low and similar between slide board and treadmill skating (18.1 [3.4] vs 18.9 [3.6] for τ [Formula: see text] and 12.6 [4.0] vs 12.4 [4.0] s for τ [HHbMb]). The [Formula: see text] ratio was not different from 1.0 (P > .05) in both conditions.
CONCLUSIONS: The fast [Formula: see text] kinetics during skating suggest that chronic adaptation to skating might overcome any possible restriction in leg blood flow during low-intensity exercise. The [Formula: see text] ratio values also suggest a good matching of O2 delivery to O2 utilization in trained speed skaters. The similar τ [Formula: see text] and τ [HHbMb] values between slide board and treadmill further reinforce the validity of using a slide board for skating testing and training purposes.