L-Arginine + L-Citrulline by EVL Nutrition | 75 Scoops

Overview: L-Arginine + L-Citrulline

These two amino acids are closely linked in the nitric oxide (NO) metabolic pathway, which regulates vascular tone, blood flow, and nutrient delivery.

• L-Arginine - Direct precursor to nitric oxide (NO).

• L-Citrulline - Converts into L-Arginine in the kidneys, thereby indirectly boosting NO levels.

When combined, they synergize to sustain higher and longer-lasting NO production than either amino acid alone.

Mechanisms of Action

Nitric Oxide Pathway

1. L-Arginine is converted by nitric oxide synthase (NOS) into nitric oxide (NO) and L-Citrulline.

2. L-Citrulline then recycles back into L-Arginine, maintaining the supply.

3. The result: Enhanced vasodilation, improved blood flow, and better nutrient/oxygen delivery to muscles and organs.
   
   

Other Biological Effects

• Improves ammonia clearance (important during exercise).

• Supports creatine synthesis, growth hormone release, and immune function.

• Enhances endothelial health and vascular elasticity.
  
  

Potential Benefits

1. Exercise Performance

• Increased endurance and strength: Better blood flow delivers oxygen and nutrients more efficiently.

• Reduced muscle fatigue: Delays buildup of lactic acid and ammonia.

• Improved recovery: Enhanced nutrient transport post-workout.

Study: Bailey et al., J Appl Physiol (2015) - Citrulline supplementation improved cycling performance and reduced perceived exertion.

2. Cardiovascular Health

• Enhances vascular function and lowers blood pressure via NO-mediated vasodilation.

• May improve arterial stiffness and endothelial function in those with hypertension or metabolic syndrome.

Study: Schwedhelm et al., Br J Clin Pharmacol (2008) - L-citrulline increases plasma L-arginine and improves endothelial function more effectively than arginine alone.

3. Erectile Function

• Supports blood flow to erectile tissue via NO signaling (similar mechanism as PDE5 inhibitors like Viagra).

• Works even better when paired with antioxidants (e.g., Pycnogenol, zinc, or ginseng).

Study: Stanislavov et al., J Sex Marital Ther (2003) - Arginine + Pycnogenol improved erectile function in 80% of men after 1 month.

4. Immune and Wound Healing Support

• Arginine enhances lymphocyte function, collagen deposition, and wound healing, particularly after surgery or trauma.

• Citrulline’s recycling effect prolongs this benefit without as much GI distress as high-dose arginine.