The Effect of Acute Quercetin Supplementation on HR, Core Temperature, and Exercise Performance

Abstract

Previous research has described a relationship between prolonged exercise in the heat and deficits in physical performance. It has also been suggested that these deficits can be attenuated by the acute ingestion of quercetin. PURPOSE: To examine the effect of acute quercetin supplementation on performance during prolonged exercise in a heated environment. METHODS: 15 college-aged males (Age = 22.1 ± 0.5 years; Wt: 79.6 ± 3.0 kg; Ht: 178.0 ± 2.0 cm; VO2Peak = 43.9 ± 1.4 mlO2/kg/min) completed 4 testing sessions. During session 1, participants completed a graded exercise test and ventilatory threshold (VT) was identified. A practice 10-km time trial on a cycle ergometer was completed in the second session. Sessions 3 & 4 involved the consumption of either 1,000 mg quercetin (Q) or a placebo (P) one hour prior to exercise. Participants rode a cycle ergometer for 2 hours at 60% VT in a heat chamber (32°C, 70% humidity). Sessions 3 & 4 were randomized and counterbalanced. The administration of the treatments was double-blind. Physiological variables (heart rate and core temperature) and perceptual variables (RPE, affect, thermal comfort, and thermal sensation) were measured every 20 minutes throughout the trial, and blood glucose was evaluated every 60 minutes. After 2 hours of exercise in the heat, each participant remained in the heated environment to complete a 10-km time trial and time to completion was recorded. RESULTS: A MANOVA revealed no differences between the conditions for any of the physiological or perceptual variables (p>.05). Similarly, there were no differences seen in time trial performance between conditions (Q: 15:09 ± 0:31; P: 15:26 ± 0:33; p>.05). CONCLUSION: The results of this investigation do not support the use of acute quercetin supplementation of this magnitude to enhance exercise performance. This work was supported by Nutravail Technologies, Chantilly, VA.