Watermelon Juice Reduces Muscle Soreness

Introduction

I always knew watermelons were great recovery food after long or hard training or racing. Why? They’re loaded with water and have a high glycemic index meaning they help replace muscle and liver carbohydrate stores well, even if you need to eat a lot of it to get the energy stores back. Here is some new research suggesting the humble watermelon may also be good for relieving muscle soreness.

The Research

Seven healthy and active sport science students (22.7 ± 0.8 yr, 68.9 ± 3.8 kg, 170.8 ± 3.6 cm) completed a repeat sprint cycling test once every five days. One hour prior to each test, they drank one of three drinks: 500 ml of natural watermelon juice (contains 1.17 grams of the amino acid citrulline), 500 ml of enriched watermelon juice (containing 6 grams of citrulline – 1.17 grams natural plus added 4.83 grams), and a placebo created to look and taste like watermelon juice. One hour after drinking the 500 ml, each subject warmed up on a cycle ergometer for 5 minutes at 75 watts then completed 8 x 30 second sprints separated by one minute of rest then a 3 minute cool down. The researchers measured heart rates during each test, blood lactate during and after the tests, and both ratings of perceived exertion (6-20 scale) and muscle soreness levels immediately after the test then 24 and 48 hours after the tests on a 1-5 scale.

The Results

There were no differences in cycling performance, ratings of perceived exertion, lactate values or heart rates during the tests. Muscle soreness was no different between the three drinks immediately after or even 48 hours after testing. However, 24 hours after testing, both the watermelon juice and enriched watermelon juice drinks resulted in lower levels of muscle soreness than the placebo drink with no difference between the two watermelon drinks.

The So What?

This Spanish study strongly suggests that (yet again) natural products such as watermelon juice can help athlete performance, in this case recovery. The theory is that the amino acids found in watermelon (citrulline and argenine) aid blood flow and decrease inflammation.  While the study used healthy active sport science students and not trained cyclists, it does suggest that as little as two cups of natural watermelon juice may help us recover from hard training or races.

Source: Tarazona-Diaz, M. and others (2013) Watermelon juice: potential functional drink for sore muscle relief in athletes.  Journal of Agricultural and Food Chemistry, 61: 7522-7528