Distance on the yo-yo intermittent recovery test is associated with flow-mediated dilatation in youth football

The Yo-Yo intermittent recovery test evaluates the individual capacity to carry out intermittent exercise leading to a maximal activation of the aerobic system. It has also been shown that aerobic exercise improves endothelial function (FMD). Moreover, studies indicate that there is a positive association between FMD and maximal oxygen uptake, but no data is available about the association with the Yo-Yo intermittent recovery test. Thus, the aim of the present study was to investigate, in young football players, whether the Yo-Yo intermittent recovery test level 1 could also be associated to the FMD. Thirteen young male football players (athletes) and eleven young male nonathletes (control) participated in this study. The FMD and Yo-Yo intermittent recovery test level 1 were measured in each group. FMD and the distance on Yo-Yo intermittent recovery test level 1 were significantly higher (P<0.002 and P<0.001, respectively) in the athletes (FMD=11.5±3.8; Yo-YoIR1= 2009.2 ± 263.8) than in control group (FMD=4.9 ± 5.4; YoYoIR1= 1420 ± 423.8). The Pearson correlation between FMD and the distance on the Yo-Yo intermittent recovery test level 1 in the athletes group was r = 0.81 (P<0.005), while in the control group it was r = 0.03 (P<0.005). Our results indicate that there is a positive association between Yo-Yo intermittent recovery test level 1 and FMD in young football players. This association strengthens the Yo-Yo intermittent recovery test level 1 as an effective tool in evaluating the performance of intermittent sports athletes.