Differences in the ventilatory thresholds in treadmill according to training status in 971 males and 301 females: a cross-sectional study

Resumen

Purpose To analyze the influence of training status on the percentage of maximum oxygen consumption, heart rate and velocity (%VO2max, %HRmax and %V-max) at which ventilatory threshold 1 and ventilatory threshold 2 occur (VT1 and VT2, respectively), in males and females separately considering age, during a ramp incremental treadmill test. Methods 791 males (36.8 +/- 9.9 years) and 301 females (33.9 +/- 11.0 years) performed a ramp incremental exercise test until fatigue where VT1 and VT2 were determined. Participants were classified as low, medium or high training status combining the oxygen consumption at VT1, VT2 and VO2max by clustering analysis. Results VO2max is poorly correlated with the %VO2max, %HRmax and %V-max at which VT1 and VT2 occur (r < 0.3), in contrast, there is a positive correlation between oxygen consumption at VT1 and VT2 with the %VO2max, %HRmax and %V-max at which VT1 and VT2, respectively, occur in males and females (r = 0.203-0.615). Furthermore, we observed the %VO2max, %HRmax and %V-max at which thresholds occur were greater the higher the training status (all p < 0.003). Conclusion The physiological determinants of the percentage of maximum at which VT1 and VT2 occur are more related to oxygen consumption at VT1 and VT2, respectively, than to VO2max. Moreover, due to the higher percentage of maximum at which VT1 and VT2 occur in individuals with a higher training status, the common strategy consisting of establishing exercise intensity as a fixed percentage of maximum might not be effective to match intensity across individuals with different training status.