Figure 4.

Outline of the experimental protocol. The 29 study subjects were first randomized by block randomization. Sixteen subjects were attributed to the BRJ group and 13 to the BRJ + VitC group. On day 1, the subjects collected morning urine, and the baseline measurements (resting blood pressure and body mass index) were performed. In the evenings of days 1 to 7, the BRJ group ingested only beetroot juice (BRJ), while the BRJ + VitC group ingested both BRJ and vitamin C (BRJ+VitC). On day 2 and 8, all subject collected a morning urine sample. On day 8, the resting blood pressure and body mass index were measured again.