Upper and lower body muscle oxygen saturation during double poling exercise at constant workloads

The purpose of this study was to investigate the effects of increasing intensity on muscle oxygen saturation (SmO2), measured in arm and leg muscles during simulated double poling (DP) at constant workloads. Nine male elite cross-country skiers with an average VO2max of 74.5 ± 3.8 ml/kg/min performed two submaximal 4‐minute DP intervals at low (LOW) and moderate (MOD) intensity, and one 3-minute all-out (MAX) interval. SmO2 was simultaneously measured in the m. triceps brachii (TB) and the m. vastus lateralis (VL) using near-infrared spectroscopy (NIRS). Mean DP power was 109 ± 16 W for LOW, 195 ± 25 W for MOD, and 286 ± 29 W for MAX, which corresponded to 47 ± 5, 77 ± 7 and 100 ± 0% of VO2peak, respectively. TB and VL showed different desaturation responses during the three intensities. End-exercise desaturation in VL showed a small decrease from LOW (0.9 ± 2.0 %) to MOD (-5.5 ± 1.6 %), as well as a large decrease from MOD to MAX (-24.3 ± 5.3 %) (all P