Determination of Aerobic Performance in Youth Soccer Players: Effect of Direct And Indirect Methods.

This study was conducted to correlate and compare values for variables determined in indirect tests with the values determined directly in youth soccer players. The study subjects were 27 youth soccer players (age 16.77 ± 0.75 years; body mass 63.29 ± 7.37 kg; body height 174.14 ± 8.46 cm) playing in the basic categories of a first division team at the regional level of Brazilian soccer. Each subject was evaluated with the following tests: a) a treadmill test to directly determine values of VO and Va (Treadmill); b) an indirect Shuttle Run Test (SRT); c) an indirect Carminatti's test (TCar). VO showed significantly different values in the Treadmill and the SRT (59.21 ± 5.88 and 50.67 ± 3.58 ml⋅kg⋅min, respectively). Similarly, values obtained for V in the treadmill test and for Va in TCar were different from values for SRT V (15.01 ± 1.10, 14.92 ± 0.87 and 12.64 ± 0.62 km⋅h, respectively). A correlation analysis showed a moderate relationship between values for V TCar and VO determined on a treadmill (r = 0.46) and Va determined on a treadmill (r = 0.54). The analysis also showed a high correlation between values of VO determined on the treadmill and VO evaluated in the SRT (r = 0.69), as well as V determined in the SRT and VO tested on the treadmill (r = 0.71), as well as between V determined in the SRT and VO evaluated on the treadmill (r = 0.77). We concluded that the SRT underestimated values of VO and Va. Additionally, V TCar showed no difference compared to Va, although it did show a low correlation with it. In addition the SRT, even with high correlations, did not seem to be a great predictor of aerobic fitness in youth soccer players.