The popular press has credited several miracle compounds with grape extracts, from curing cancer to reversing ageing. 

However, even though these claims might be a little premature, several health and wellness benefits are associated with grapes. For example, sports scientists prove that grape compounds can improve physical performance and recovery.

This study aimed to examine the effects of combined grape seed extract and L-citrulline supplementation on cardiovascular responses to exercise in young males.

History of Grape Seed Extract & L-Citrulline

A legacy sports nutrition ingredient, L-citrulline has been studied since the 1980s for its performance benefits. However, the primary use has been attributed to nitric oxide, which increases blood flow via dilated peripheral blood vessels and nitric oxide levels.

The popularity of L-Citrulline can be attributed to many reasons. One of the few substances that benefit the human body, it is widely used in bodybuilding supplements. Additionally, it enhances the pump, so your body looks even better after a workout session. 

Grape seed extract protects the body from free radicals that can cause damage to it. It improves circulation and can improve muscle growth and recovery. Therefore, it is ideal for bodybuilders. The grape seed extract is also a natural source of antioxidants that can help the body recover from strenuous exercise.

You can use grape seed extract to replenish your muscles if you’ve taken a beating. It helps to reduce oxidative stress, inflammation, and muscle damage.

Grape Seed Extract supplementation can significantly limit the damage to muscle tissue during hefty strength training sessions. Korean researchers suspect this may mean they experience less muscle soreness and recover more rapidly.

A randomized, double-blind, placebo-controlled study conducted on 40 female volleyball players aged 14 to 42 assessed the effects of grape seed extract (GSE) supplementation on oxidative stress biomarkers. The study showed that administration of GSE for eight weeks in female volleyball players showed positive effects on some biomarkers of oxidative stress and insulin metabolism parameters.


Increasing nitric oxide bioavailability (NO) and endothelial-mediated vasodilation through grape seed extract (GSE) or L-citrulline supplements has enhanced endothelial-mediated vasodilation. 

For this study, the experts recruited young, healthy males to examine the additive effects of combining the two supplements on hemodynamic responses to dynamic exercise. 

In a seven-day study, the effects of 1) GSE + L-citrulline, 2) GSE, 3) L-citrulline, and four researchers examined) placebo supplementation on systolic, diastolic, mean arterial blood pressures (MAPs), cardiac output, total vascular conductance (TVC), and oxygen (O2) consumption at rest and during cycling exercise. 

Result of The Study

As compared to placebo, GSE, L-citrulline, and combined supplementation did not decrease SBP, DBP, and MAP, while cardiac output and TVC were increased only at 80% workload (p = 0.05), GSE and combined supplementation did not significantly increase VO2 across workloads (p = 0.05). 

However, these variables did not show additive benefits. The researchers concluded that supplementing with GSE, L-citrulline, and combined supplements increased cardiac output partially due to decreased vascular resistance. The researchers concluded that GSE could be an ergogenic aid that can improve oxygen delivery to exercising muscles.

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