Sore from the gym after a good bout of high intensity endurance exercise? Maybe you should try watermelon juice. Research suggests that a non-essential protein found in watermelon can help reduce muscle sorness after exercise. Here’s how it works.

Reduced Muscle Soreness and Watermelon Juice

Watermelon, not only is it a delicious treat on a hot summer day but it’s also packed full of a protein called L-Citrulline. L-Citrulline is a non-essential protein meaning we don’t need to necessarily get it through our diet because our bodies make it on their own. However, getting more of it through our diet isn’t necessarily a bad thing. Researchers have found that watermelon (which is one of the few foods high in natural L-Citrulline) can have benefits to help relieve post-exercise muscle soreness.

How L-Citrulline Works

L-Citrulline assists with nitric oxide production. Nitric oxide is responsible for increased blood flow. L-Citrulline may help muscles get more nutrients to areas of the muscle requiring those nutrients and helping to reduce muscle sorenss.

The Effectiveness Of Watermelon At Reducing Muscle Soreness

Researchers took seven men with the average age of 22 and an average BMI of 24 (which is within the “normal” range). The men were not competetive athletes but they participate regularly in regular exercise. The men also had no other medical history and took no prescription medications. Prior to the test the men had no vigorous exercise and were limited from consuming any alcohol or stimulants. Before the test they had a meal rich in carbohydrates. About an hour before the test, they all drank half a liter of watermelon juice. One drink was with natural watermelon juice with no extra Citrulline added (about 1.73g of Citrulline), one drink was enhanced with 6g of Citrulline, and the last drink was a placebo drink with watermelon flavoring and no Citrulline added.

The men next began a series of cycling tests to stimulate physical activity and to increase physical exertion. After each cycling tests the men then reported their soreness 24 hours afterwards and then 48 hours after the physical activity with each trial of exercise and type of juice consumed.

What they Found About Watermelon Juice and Muscle Soreness

Interestingly, although one type of juice contained an added amount of Citrulline, it was not as easily absorbed as just the plain, regular, watermelon juice. So even though levels of Citrulline were higher, they weren’t as effectively absorbed. For the fake watermelon juice, muscle soreness was significantly higher twenty-four hours after exercise than when compared to the others. Also interesting, even though the natural watermelon juice was absorbed better, the natural juice and the juice with additives did not differ in the way they reduced muscle soreness.

Give Watermelon Juice A Try

Although this study does have its limitations (small sample size, type of exercise performed, relatively young and healthy participants – who were only male, and other dietary factors to name a few), the results are consistant with other studies suggesting that L-Citrulline does play a part in helping to reduce muscle soreness. Give it a try, see if it works for you, if not, watermelon juice by any means certainly is going to add some tremendous benefits through vitmamins and antioxidants.

How Much Watermelon Juice Is Needed: If you’re juicing your own watermelon, you’ll need about four to six cups of watermelon before it’s juiced down (about a third of a regular sized watermelon or an entire small watermelon). One cup of regular watermelon contains about 250mg of L-Citrulline. If you’re going for watermelon juice already made, make sure it’s all natural with no sweeteners etc.

Have you ever used watermelon juice for exercise? How did it work for you?

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1. Aguayo, E., Alacid, F., Carrasco, M., Tarazona-Diaz, M. “Watermelon Juice: Potential Functional Drink For Sore Muscle Relief In Athletes.” Journal of Agriculture and Food Chemistry. 20 Nov. 2013. Web. 8 April 2014.
2. Perkins-Veazie, P., Rimando, A. “Determination Of Citrulline In Watermelon Rind.” Journal of Chromatography. 17 June 2005. Web. 9 April 2014.