This study was a randomized, double-blind, crossover design for 3 weeks. In the first week, a researcher explained all the experimental procedures to the participants. In the following two weeks, the participants attended the Exercise Physiology laboratory to be assessed in 2 rowing ergometer sessions, separated from each other by a washout period of 7 days, under the same environmental conditions.

In both strictly identical sessions, the participants randomly ingested beetroot juice (BRJ) or placebo (PL) 3 hours before the start of the tests.

Three hours after BRJ or PL intake, the participants began the 2,000-meter rowing ergometer test. Before starting (pretest) and at the end of the tests (posttest), blood oxygen saturation, rating of perceived exertion (RPE), and blood lactate measurements were taken. During the rowing ergometer tests, performance parameters and cardiorespiratory variables were recorded.

Inclusion Criteria:

1. national and/or international level;
2. without cardiovascular, respiratory, metabolic, neurological or orthopedic disorders that may affect the performance of the rowing ergometer test;
3. no consumption of drugs or medicines;
4. no smoking;
5. Informed consent to participate in the study signed by all rowers

Exclusion Criteria:

1. Ingestion of nutritional supplements taken in the three months prior to the start of the study;
2. no following the guidelines established by the nutrition professional.

well-trained male master rowers