Comparison between continuous incremental ramp test and discontinuous square-wave test for vVO2max assessment in long distance runners and soccer players

Aim: In treadmill testing, the running velocity associated with maximum oxygen uptake (vVO2max) is largely utilized for both laboratory testing and training on the field. Differences between a continuous incremental ramp test (R1) and a discontinuous square wave tests (SW) in vVO2max assessment have been already described. Long distance runners and soccer players are both athletes involved with running. However, the physiological demands are different: in runners are continuous while in soccer players are discontinuous, with an alternation of aerobic and anaerobic tasks. Therefore, the aim of the study was to compare the vVO2max difference between R1 and SW in both these athletes. Hypothesis is that, this difference should be higher in soccer players than in runners, due to a different capacity to adjust the oxygen transport system at each workload. Method: Eight runners (RUN) and nine soccer players (SOC) reported to the laboratory twice to perform two maximum incremental tests: R1 (1 km/h per min) and SW (workloads of 4 min each, with 5 min of rest in between), in random order, on a motorised treadmill for VO2max and vVO2max assessment. At rest and during exercise, cardiorespiratory and metabolic parameters were collected breath-by-breath. Blood lactate concentration [La-] was measured at rest and at maximum exercise. Results: No significant differences between groups and protocols were found in VO2max (SOC: 3892±104 vs 3922±423 ml/min; RUN: 4159±115 vs 4170±116, for SW and R1, respectively), as well as in VE, VCO2, [La-]peak and HR at maximum exercise. However, vVO2max was significantly higher in R1 compared to SW in both groups (SOC: 16.1±0.3 vs 19.4±0.4 km/h, RUN: 19.5±0.3 vs 22.1±0.3 km/h, for SW and R1, respectively; P<0.05), with a higher difference between R1 vs SW in SOC than RUN (+21% vs +13%, respectively; P<0.05). Conclusion: Despite similar VO2max values, vVO2max was higher in R1 than in SW in both groups. However, the difference was significantly higher in SOC than RUN, possibly due to a slower capacity to adjust the oxygen transport system to a given workload in SOC. Even though the two protocols can be used to assess VO2max, the vVO2max differences between protocols must be acknowledged to prescribe correctly high intensity training, especially for soccer players.