It’s summertime and we’re going to have to beat the heat these days. One way to beat the heat with your nutrition is by adding ingredients to your day that leave you feeling refreshed.
Watermelon is a rich source of l-citrulline, a non-essential amino acid that functions as a precursor for nitric oxide synthesis. 
In addition, watermelon is also rich in lycopene, an antioxidant potentially present in watermelon, tomato, guava etc.
Due to its rich nutritional profile and allied health benefits like containing potassium, magnesium, and amino acids which work to maintain the health of:
Blood vessels and ensure smooth blood flow
Maintaining acid-based balance in the body, which helps lower the risk of higher blood pressure
Reducing cancer insurgence, diabetes, and macular diseases
Improve cardiovascular health ,
Help lower inflammation 
Help with muscle soreness 
In a in vitro study, seven athletes were supplied with 500 mL of natural watermelon juice, enriched watermelon juice and placebo. Both watermelon juices helped to reduce the recovery heart rate and muscle soreness after 24 h. 
So, this summer stock up on your produce by adding watermelon to your grocery list.
Hong MY, Hartig N, Kaufman K, Hooshmand S, Figueroa A, Kern M. Watermelon consumption improves inflammation and antioxidant capacity in rats fed an atherogenic diet. Nutr Res. 2015;35(3):251‐258. doi:10.1016/j.nutres.2014.12.005
Lum T, Connolly M, Marx A, et al. Effects of Fresh Watermelon Consumption on the Acute Satiety Response and Cardiometabolic Risk Factors in Overweight and Obese Adults. Nutrients. 2019;11(3):595. Published 2019 Mar 12. doi:10.3390/nu11030595
Naz A, Butt MS, Sultan MT, Qayyum MM, Niaz RS. Watermelon lycopene and allied health claims. EXCLI J. 2014;13:650‐660. Published 2014 Jun 3.
Tarazona-Díaz MP, Alacid F, Carrasco M, Martínez I, Aguayo E. Watermelon juice: potential functional drink for sore muscle relief in athletes [published correction appears in J Agric Food Chem. 2013 Nov 20;61(46):11241]. J Agric Food Chem. 2013;61(31):7522‐7528. doi:10.1021/jf400964r