17th Annual ECSS-Congress, Bruges 2012

Abstract details

Abstract-ID: 703
Session: [MO-PM03] Nutrition and supplements
Lecture room: and/South
Date & time: 06.07.2017 / -
Title of the paper: Does multiday dietary nitrate supplementation have an ergogenic effect on intermittent exercise performance and oxygen parameters?
Authors: Appel, K., Härter, E., Stöcker, F., Schulz, T.
Institution: Technical University Munich
Department: Department of Sport and Health Science
Country: Germany
Abstract text Introduction Dietary Nitrate (NO3-) supplementation has been reported to elicit many ergogenic effects in humans, for instance, to reduce the 02 cost of submaximal exercise and to increase tolerance to high-intensity exercise . Therefore, the aim of this study was to examine the ergogenic effect of NO3- supplementation via beetroot on exercise performance (power output, repeated sprint ability) and oxygen parameters during a session of high intensive sprint interval training (SIT). Methods Thirteen healthy, recreationally active men (aged 17-34 yrs, VO2peak 51.77 ± 5.80 ml/min/kg) participated in this study. In a randomized, double blinded, crossover design subjects received either NO3- rich (70ml/day, containing 0.4 - 0.45 g of NO3-) or depleted (70ml/day, containing <1.26 mg of NO3-) beetroot juice for a six day period. On day six, the subjects completed a SIT test consisting of 3-5 x 30 seconds „all out“ cycling sprints interspersed by four minutes of passive recovery. Power output ( Pmean, Ppeak), blood lactate and oxygen uptake (VO2) were recorded. Relative changes in oxygenated (∆O2Hb) and deoxygenated (∆HHb) hemoglobin were calculated using near-infrared spectroscopy (NIRS) of the left vastus lateralis muscle. Results Compared to placebo (PL), nitrate supplementation (BR) elicited higher mean and peak power output (Pmean BR: 625.00 ± 78.16 vs. PL: 609.13 ± 82.12 W; Ppeak: BR: 936.05 ± 129.16 vs. PL: 905.21 ± 117.33 W, both p>.05), while none of the enhancement between sprints was statistically significant. The decrease of power was significantly attenuated in between the 1st and 2nd interval by nitrate (BR: 16.6 ± 5.6% vs. PL: 18.9 ± 6.3%; p<.05), whereas the decline within each interval did not change (p<.05). Oxygen uptake during sprints was slightly elevated in BR (46.16 ± 5.91; 48.96 ± 5.26; 47.78 ± 4.56 ml/min/kg) compared to PL (44.39 ± 7.13; 46.20 ± 6.98; 45.00 ± 5.78 ml/min/kg; p >.05). Muscle oxygenation (∆ HHb, ∆ O2Hb), as well as metabolic response (lactate) remained unchanged between conditions in the three subsequent SIT. Discussion The trends in power output support the beneficial effects of nitrate supplementation on performance, as well as the higher repeated sprint ability after the first two intervals. The lack of effect in muscle oxygenation corresponds to actual research, as well as the statistically non relevant changes in VO2. Dietary Nitrate (NO3-) supplementation seems to have an effect on repeated sprint ability in SIT and may therefore result in enhanced training adaptions and higher performance improvement in long term. Nevertheless, this change can not be explained by oxidative or metabolic processes. There might be other factors influencing intermittent exercise performance more, e.g. cognitive parameters. Contact katharina.appel@web.de
Topic: Nutrition
Keyword I: nitrate
Keyword II: performance
Keyword III: oxygenation