Comparison of Watermelon and Carbohydrate Beverage on Exercise-Induced Alterations in Systemic Inflammation, Immune Dysfunction, and Plasma Antioxidant Capacity

Abstract

Consuming carbohydrate- and antioxidant-rich fruits during exercise as a means of supporting and enhancing both performance and health is of interest to endurance athletes. Watermelon (WM) contains carbohydrate, lycopene, l-citrulline, and l-arginine. WM may support exercise performance, augment antioxidant capacity, and act as a countermeasure to exercise-induced inflammation and innate immune changes. Trained cyclists (n = 20, 48 ± 2 years) participated in a randomized, placebo controlled, crossover study. Subjects completed two 75 km cycling time trials after either 2 weeks ingestion of 980 mL/day WM puree or no treatment. Subjects drank either WM puree containing 0.2 gm/kg carbohydrate or a 6% carbohydrate beverage every 15 min during the time trials. Blood samples were taken pre-study and pre-, post-, 1 h post-exercise. WM ingestion versus no treatment for 2-weeks increased plasma l-citrulline and l-arginine concentrations (p < 0.0125). Exercise performance did not differ between WM puree or carbohydrate beverage trials (p > 0.05), however, the rating of perceived exertion was greater during the WM trial (p > 0.05). WM puree versus carbohydrate beverage resulted in a similar pattern of increase in blood glucose, and greater increases in post-exercise plasma antioxidant capacity, l-citrulline, l-arginine, and total nitrate (all p < 0.05), but without differences in systemic markers of inflammation or innate immune function. Daily WM puree consumption fully supported the energy demands of exercise, and increased post-exercise blood levels of WM nutritional components (l-citrulline and l-arginine), antioxidant capacity, and total nitrate, but without an influence on post-exercise inflammation and changes in innate immune function.

The Effect of Watermelon Beverage Ingestion on Fatigue Index in Young-Male, Recreational Football Players

“…We used watermelon beverage considering the fact that watermelon is the richest food source of citrulline (12). We were not able to find any published data regarding citrulline content in other foods except Fish (14).…”

“…Citrulline is also available in natural sources besides supplementation. Watermelon, the second highest in production and harvested fruit in the world (11), is the richest source of citrulline (12). Moreover, a study showed that citrulline bioavailability in the watermelon was greater than those in the pharmacological formulation (13).…”

Modulating Oxidative Stress and Inflammation in Elders: The MOXIE Study

“…Sample size for mechanistic outcomes were based on lycopene as the bioactive food compound in greatest concentration in watermelon (82, 83). Sample size calculations for clinical outcomes were based on official guidelines from the Brachial Artery Reactivity Task Force; a sample size of 20–30 participants is indicated to detect changes in FMD with a crossover design (84).…”

Alimentos vs. suplementos fontes de carboidratos: Efeitos na performance

“…Considerando que os efeitos do suco de melancia não parecem ocorrer quando a fruta é ingerida 1 a 2 h antes do exercício, Shanely et al 15 testaram o efeito da suplementação com suco de melancia por um período mais prolongado. Os autores avaliaram o efeito da ingestão de um purê de melancia sem caroço, obtido a partir do suco congelado (980 ml contendo 0,2 g/kg de carboidrato, 1,47 g de L-citrulina e 0,465 g de L-arginina) em relação a uma bebida contendo carboidratos a 6% (Gatorade).…”