Watermelon juice helps ease post-workout muscle pain. Research published in the Journal of Agricultural and Food Chemistry found that L-citrulline (watermelon is rich in this amino acid) helps reduce recovery heart rate and muscle soreness. Look for watermelon juice in health-food stores-but check that it’s not just a watermelon-flavoured drink with lots of added sugar. Better yet, make your own by throwing chunks of seeded watermelon into a blender; whirl, and strain out any pulp. You can also try our Watermelon Bliss smoothie recipe.