Under these circumstances, quercetin is an effective sports supplement
If athletes are short on calories and also have little recovery time, they can significantly increase their endurance by supplementing with a gram of quercetin per day.
Quercetin supplements improve endurance. According to meta-studies, the effect is statistically significant, but small - too small to be relevant to athletes. [Int J Sport Nutr Exerc Metab. 2013 Feb;23(1):73-82.]
Researchers from China Medical University in Taiwan published a small human study in Frontiers in Nutrition in 2022, in which 12 male students participated as test subjects.
The students were healthy and physically active, but they were not trained athletes.
The researchers invited the test subjects to their laboratory twice. Both times they had to cycle on an empty stomach for an hour at an intensity of 70 percent of their maximum oxygen uptake, then, after the first session, eat a light meal and climb on the bike again three hours. This time they had to cycle at 75 percent of their maximum oxygen uptake until they literally couldn't anymore.
On one occasion, the students took 2 capsules containing 500 milligrams of quercetin every day at breakfast for 7 days prior to the session. In total, that amounted to 1000 milligrams of quercetin. The researchers used a product from GNC.
On another occasion, the students took a placebo with breakfast for 7 days.
Quercetin supplementation extended the time that the subjects were able to continue riding during the second more intensive cycling session by 21 percent.
Supplementation had virtually no effect on the amount of fat and glucose the students consumed during the trial. However, supplementation did ensure that after the first session and the meal that followed, the insulin level rose less.
Apparently, the body uses insulin more efficiently by supplementing with quercetin.
In addition, quercetin increased the total activity of the antioxidants in the blood [TAC]. In addition, the researchers saw less creatine kinase [CK] and less inflammatory factor interleukin-6 appear in the blood of the supplemented subjects after the second session. This indicates less muscle damage.
"The beneficial effects of quercetin are likely due to its glucogenic, antioxidant, and anti-inflammatory properties", summarize the Taiwanese.
"Thus, shortterm quercetin supplementation may be considered an effective ergogenic aid for enhancing high-intensity cycling performance among young adults."
Front Nutr. 2022 Apr 28;9:875319.
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