the distance in the 6-MRT compared to baseline

the distance in the 6-MRT compared to baseline

the distance in the 6-MRT compared to baseline

On day 1, all participants completed the 6-MRT corresponding to baseline. Then, on days 2 and 3, each participant performed the 6-MRT with 30 mg·kg-1 and 45 mg·kg-1 of BA (low and high-dose trials, respectively). BA was purchased in powder format from a factory specializing in sports supplements. BA was colorless when diluted in water and had a characteristic taste. This format of BA (powder) allowed personalized dosing for each participant. The research team performed the personalized dosing before the application of the treatment. Between the evaluation days, there was 72 hours difference. The 30 mg·kg-1 or 45 mg·kg-1 BA administration was done with a double-blind method. Thus, on day 2, 50% of the sample performed the 6-MRT supplemented with 30 mg·kg-1 BA, while the other 50% performed the 6-MRT with 45 mg·kg-1 BA. On day 3, those participants who completed the 6-MRT with 30 mg·kg-1 BA now performed with 45 mg·kg-1 BA and vice versa.

The test was performed on an official 400 m athletic track simultaneously every measurement day (09:00 - 11:00 a.m.) and under similar climatic conditions (temperature = 16 - 18° C and relative humidity = 70 - 80%). Also, to simulate the reality of the competition, the 6-MRT was performed in subgroups of three participants. These subgroups were maintained throughout the intervention, modifying only the dose of BA ingested.

A lactometer (h/p/cosmos®) was used to measure capillary [La]. This lactometer generates an enzymatic-amperometric detection of lactate with an accuracy of ± 3% (minimum standard deviation of 0.2 mmol·L-1), sample volume 0.2 μL, and with a measurement range of 0.5-25.0 mmol·L-1.