1. Results (cont’d) Results BACKGROUND: It has been reported that dietary nitrate supplementation effectively reduces blood pressure and increases tolerance of both moderate and high intensity exercise. However, it is presently unknown whether these effects are solely seen during long term supplementation or are equally present following short term supplementation; thus, the purpose of this study was to examine the effects of short term nitrate supplementation on exercise performance. METHODS: All subjects were asked to complete a maximal exercise test following the Bruce protocol on two occasions, once after ingesting 300 ml of beetroot juice and again following consumption of 300 ml of black cherry juice. Subjects were randomly assigned which juice to consume when and the exercise test was administered 2.5 h following ingestion. The statistical analysis used was the t-test and the alpha level was set at p<0.05. RESULTS: Demographic data were as follows: Males (n=2, age=26 + 8.5 yrs, height=191 + 7.8 cm, weight=88.5 + 19.09 kg). Females (n=3, age=21.3 + 0.58 yrs, height=162.67 + 6.81 cm, weight=54 + 8.72). Time to exhaustion was extended (PL: 642.6 + 39.7 vs. BR: 764.8 + 75.3 sec, p<0.05). In addition, both resting SBP (PL: 113 + 9 vs. BR: 107 + 9 mmHg, p<0.01) and maximum exercise SBP (PL: 185 + 10 vs BR: 178 + 10 mmHg, p<0.01) were significantly reduced following beet juice consumption. CONCLUSION: This study supports the notion that acute dietary nitrate supplementation can significantly improve exercise performance and effectively reduce SBP both at rest and during exercise. Abstract Conclusions I. Nduka. Sponsor: Judy R. Wilson, Ph.D. Cardiovascular Research Laboratory, The University of Texas at Arlington, Arlington, TX. Acute Effects of Dietary Nitrate Supplementation Via Beetroot Juice on Exercise Performance The purpose of this study was to examine the effects of short term nitrate supplementation via beetroot juice on exercise performance. Participants were asked to consume 300 ml of beetroot juice or 300 ml of black cherry juice 2.5 hours prior to reporting to the laboratory on two separate occasions. Visits were separated by at least one day and the order of the drinks participants consumed was randomized. When subjects reported to the lab, their height and weight was obtained. Then a heart rate monitor was attached to their chest to allow measurement of heart rate. This signal was sent to a watch and the heart rate was read from there. The subject then stood on the treadmill. A blood pressure cuff was attached to their upper arm and blood pressure was taken during each workload along with a rate of perceived exertion score (RPE) with ratings from 6 (rest) to 20 (maximal exercise). The treadmill protocol increased speed and elevation every three minutes until the subject could not go any further. Subjects were allowed to communicate with hand signals. A "thumbs up" indicated continuing to exercise, a "waggle" of the hand, palm down, indicated not much longer. Subjects were then asked to continue “another 30 sec” or “into the next workload” prior to stopping. This allowed the researcher to collect final or maximal values. The treadmill was then sent into recovery mode and subjects were allowed to slow down while heart rate and blood pressure continued to be monitored. When their heart rate dropped below 120 bpm and/or their systolic blood pressure was below 130 mmHg and the subject felt recovered, they were allowed to leave. MaleFemale Age (yrs)26 + 8.521.3 + 0.58 Height (cm)191 + 7.8162.67 + 6.8 Weight (kg)88.5 + 19.0954 + 8.72 Table 1. Demographic table. Purpose Methods Figure 1. Differences in time to exhaustion between the test in which the placebo was administered and that in which beetroot juice was administered. Figure 2. Differences in resting systolic blood pressure between the test in which the placebo was administered and that in which beetroot juice was administered. Figure 3. Differences in maximum exercise systolic blood pressure between the test in which the placebo was administered and that in which beetroot juice was administered. Supplementation of dietary nitrates via beetroot juice significantly improves exercise tolerance to maximal exercise. Beetroot juice supplementation also effectively reduces resting systolic blood pressure as well as maximum exercise systolic blood pressure.