Testing protocol affects the velocity at VO2max in semi-professional soccer players

To compare three different protocols to assess the velocity associated with the maximal oxygen uptake (V-max) in soccer players. Sixteen semi-professional soccer players performed three maximum incremental tests on treadmill: two continuous protocols [1 km center dot h(-1)center dot min(-1) (CP1); and 1 km center dot h(-1) every 2 min (CP2)], and one discontinuous (DP) protocol to determine V-max, maximum oxygen uptake (VO2max) and oxygen cost of running (i.e., the slope of the VO2 vs velocity relationship at submaximal exercise). V-max was higher in CP1> CP2> DP (19.4 +/- 1.7, 17.4 +/- 1.2, 16.1 +/- 1.1 km center dot h(-1) for CP1, CP2, and DP, respectively; P < 0.05 ES: 0.09 to 3.36). No difference in VO2max was found between CP1, CP2 and DP (P > 0.05). Oxygen cost of running showed between-protocol differences (CP1> CP2> DP; P < 0.05; ES: 0.28 to 3.30). V-max was higher when determined using continuous vs discontinuous protocols due to the greater overestimation in oxygen cost of running. Such differences in V-max should be considered to optimize acute physiological responses during high-intensity running activities.