No Effect of Acute and 6-Day Nitrate Supplementation on VO2and Time-Trial Performance in Highly Trained Cyclists.
While the majority of studies reporting ergogenic effects of dietary nitrate have used a multiday supplementation protocol, some studies suggest that a single dose of dietary nitrate before exercise can also improve subsequent performance. We aimed to compare the impact of acute and 6-day sodium nitrate supplementation on oxygen uptake (V̇O2) and time-trial performance in trained cyclists. Using a randomized, double-blind, cross-over design, 17 male cyclists (25 ± 4 y, V̇O2peak65 ± 4 ml·kg-1·min-1, Wmax411 ± 35 W) were subjected to 3 different trials; 5 days placebo and 1 day sodium nitrate supplementation (1-DAY); 6 days sodium nitrate supplementation (6-DAY); 6 days placebo supplementation (PLA). Nitrate was administered as 1097 mg sodium nitrate providing 800 mg (~12.9 mmol) nitrate per day. Three hours after ingestion of the last supplemental bolus, indirect calorimetry was performed while subjects performed 30 min of exercise at 45% Wmaxand 30 min at 65% Wmaxon a cycle ergometer, followed by a 10 km time-trial. Immediately before exercise, plasma [nitrate] and [nitrite] increased to a similar extent during the 6-DAY and 1-DAY trial, but not with PLA (plasma nitrite: 501 ± 205, 553 ± 278, and 239 ± 74 nM, respectively; p < .001). No differences were observed between interventions in V̇O2during submaximal exercise, or in time to complete the time-trial (6-DAY: 1004 ± 61, 1-DAY: 1022 ± 72, PLA: 1017 ± 71 s; p = .28). We conclude that both acute and 6-days of sodium nitrate supplementation do not alter V̇O2during submaximal exercise or improve time-trial performance in highly trained cyclists, despite increasing plasma [nitrate] and [nitrite].
Jean M
JM
Nyakayiru
Kristin L
KL
Jonvik
Philippe J M
PJ
Pinckaers
Joan
J
Senden
Luc J C
LJ
van Loon
Lex B
LB
Verdijk
D000328:Adult; D056352:Athletes; D054874:Athletic Performance; D001642:Bicycling; D001794:Blood Pressure / Q000187:drug effects; D015992:Body Mass Index; D018592:Cross-Over Studies; D019587:Dietary Supplements; D004311:Double-Blind Method; D015444:Exercise; D041981:Gastrointestinal Tract / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D008297:Male; D009566:Nitrates / Q000008:administration & dosage* / Q000097:blood; D009573:Nitrites / Q000097:blood; D010101:Oxygen Consumption / Q000187:drug effects*; D058573:Performance-Enhancing Substances / Q000008:administration & dosage*; D055815:Young Adult
D009566:Nitrates; D009573:Nitrites; D058573:Performance-Enhancing Substances; C031618:sodium nitrate
ergogenic aid; nitrite; sodium nitrate