If you’re looking for a refreshing exercise drink, try fresh watermelon juice. In a new Spanish study published in the Journal of Agricultural and Food Chemistry, participants who drank 17 ounces of watermelon juice an hour before strenuously cycling had less muscle soreness 24 hours later than when they drank a placebo beverage.
The researchers attributed the benefit to L-citrulline, an amino acid found in high levels in watermelon (but few other foods). Juice enhanced with extra L-citrulline provided no extra benefits, suggesting that the amount naturally present is sufficient. Moreover, the L-citrulline was found to be best absorbed by the body from natural (unpasteurized) watermelon juice. Though some athletes drink watermelon juice to enhance their performance, this study found no effect on pedaling speed, perceived exertion or heart rate.