Testing protocol affects the velocity at VO in semi-professional soccer players.

To compare three different protocols to assess the velocity associated with the maximal oxygen uptake (V) in soccer players. Sixteen semi-professional soccer players performed three maximum incremental tests on treadmill: two continuous protocols [1 km·h·min (CP1); and 1 km·h every 2 min (CP2)], and one discontinuous (DP) protocol to determine V, maximum oxygen uptake (VO) and oxygen cost of running (i.e., the slope of the VO vs velocity relationship at submaximal exercise). V was higher in CP1> CP2> DP (19.4 ± 1.7, 17.4 ± 1.2, 16.1 ± 1.1 km·h for CP1, CP2, and DP, respectively; < 0.05 ES: 0.09 to 3.36). No difference in VO was found between CP1, CP2 and DP (> 0.05). Oxygen cost of running showed between-protocol differences (CP1> CP2> DP; < 0.05; ES: 0.28 to 3.30). V was higher when determined using continuous vs discontinuous protocols due to the greater overestimation in oxygen cost of running. Such differences in V should be considered to optimize acute physiological responses during high-intensity running activities.