The beneficial effects of beetroot juice supplementation (BJS) have been tested
during cycling, walking, and running. The purpose of the present study was to investigate
whether BJS can also improve performance in swimmers. Fourteen moderately trained
male master swimmers were recruited and underwent two incremental swimming tests
randomly assigned in a pool during which workload, oxygen uptake (VO2), carbon dioxide
production (VCO2), pulmonary ventilation (VE), and aerobic energy cost (AEC) of
swimming were measured. One was a control swimming test (CSW) and the other a
swimming test after six days of BJS (0.5l/day organic beetroot juice containing about 5.5 mmol
of NO3−).
Results show that workload at anaerobic threshold was significantly increased by
BJS as compared to the CSW test (6.3 ± 1 and 6.7 ± 1.1 kg during the CSW and the BJS
test respectively). Moreover, AEC was significantly reduced during the BJS test (1.9 ± 0.5
during the SW test vs. 1.7 ± 0.3 kcal·kg−1·h−1 during the BJS test).