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Peer-Reviewed Article

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Ingestion of dark chocolate (DC), a dietary source high in flavanols, may increase nitric oxide bioavailability. Elevating blood nitric oxide concentrations may augment metabolic efficiency by reducing the amount of oxygen or energy needed to perform a given task. Utilizing a crossover design, the purpose of this study was to investigate the effect of acute ingestion of DC on running economy (RE). Nineteen recreationally trained females (age: 20±1 years) volunteered for this investigation, with 16 completing all procedures (n = 16). Two-hours before RE assessment, participants consumed either 42.5 g of DC or an isocaloric amount of white chocolate (WC) (37.2 g) with a 34 mg caffeine pill. Participants ran on the treadmill at 2.68 m/s for 10-minutes to assess RE. However, only the last 5-minutes of the test were used for oxygen utilization (VO2), energy expenditure (EE), and respiratory exchange ratio (RER) determination via indirect calorimetry. Identical testing procedures were utilized for DC and WC treatments with a seven-day washout period separating trials. A repeated measure paired t-test was used to determine differences between dependent variables with statistical significance set at p < 0.05. There were no significant mean differences (ps > 0.05) between trials for VO2, EE, or RER. In conclusion, supplementation of DC 2-hours prior to steady state running had no effect on RE or fuel utilization compared to an isocaloric serving of WC in recreational female runners.


At the time this article was written, Bianca De Lucia was a graduate student in the College of Health professions at Sacred Heart University.

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Creative Commons Attribution 4.0 International License
This work is licensed under a Creative Commons Attribution 4.0 International License.



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