Comparison between the direct and indirect methods of VO_2máxdetermination in runners

INTRODUCTION:

direct tests are considered "gold standard" for determining physiological variables. However, the financial cost is high and there is the need of skilled labor for its operation. Thus, the indirect tests are used by most professional of Physical Education as an affordable alternative to the lack of direct measurement.

OBJECTIVE:

to compare the values of maximum consumption of oxygen (VO_2max), determined directly by a system with spirometry values determined from indirect protocols.

METHODS:

15 male individuals participated (27.4 ± 3.5 years), physically active, who performed the incremental test on treadmill for the direct determination of VO_2max with the gas analyzer. The tests for the prediction of VO_2max were ErgoPC; Polar Fitness Test, test bank and Cooper. We used descriptive statistics (mean ± standard deviation - SD); the sphericity was tested by Mauchly's test, the methods were compared by ANOVA of repeated measurements, with Bonferroni adjustment for multiple comparisons. Data normality was evaluated by the Shapiro-Wilk test, and the Pearson correlation coefficient was also applied, adopting a significance level of p <0.05.

RESULTS:

the average VO_2max was determined directly from 55.8 ± 6.1 ml • kg ^-1 • min^-1 and the values for the indirect tests, the percentage of underestimation and correlation coefficient were, respectively: 33.7 ErgoPc ± 4.5 ml • kg ^-1 • min^-1 (39.6%, r = 0.71, p <0.001); Polar Fitness Test 53.2 ± 6.4 ml • kg ^-1 • min^-1(4.6%, r = 0.64, p = 0.774); bank test 48.8 ± 6.3 ml • kg ^-1 • min^-1 (12.5%, r = 0.60, p = 0.001 ) and Cooper 43.9 ± 7.9 ml • kg ^-1 • min^-1 (21.4%, r = 0.65, p <0.001).

CONCLUSION:

the indirect methods may suggest overload in lower or higher training for required physiological adaptations and only the Polar Fitness Test showed no difference statistically significant.

protocols; male; spirometry