Citrulline is an amino acid that’s converted to L-arginine in the body, during the urea cycle and alongside L-ornithine. Supplementing with citrulline is actually a more effective way to raise arginine levels and enhance nitric oxide (NO) production in the body than supplementing with arginine itself.
How Does Citrulline Work?
Citrulline is converted to L-arginine in the kidneys and increases the level of L-arginine in blood plasma. L-arginine is then readily available to feed into the nitric oxide synthase (NOS) pathway of NO production. Arginine is converted into NO and increases blood flow and nutrient delivery to working muscles. Citrulline also plays a role in ATP production when energy demand increases. It also helps buffer the buildup of ammonia in muscle, which reduces exercise fatigue and increases workout endurance!
Why Choose Citrulline Malate?
There are two main types of citrulline being used in sports supplements: citrulline malate (CM) and L-citrulline. CM is citrulline attached to a molecule of malic acid. The best form of CM come in a ratio of 2:1 (two molecules of citrulline to one molecule of malic acid). Based on the body of research conducted on citrulline and CM, it appears that CM is more effective in producing improvements in exercise performance (i.e., endurance, strength, etc). Both forms of citrulline appear to be effective at increasing NO and muscle pumps.
Benefits of Citrulline
Citrulline can help increase blood flow and nutrients to working muscles, maintain nitrogen balance in the muscles, increase energy levels, reduce fatigue and post-workout muscle soreness, and enhance endurance during exercise!
Increase Energy and Endurance
Citrulline can modulate enzymes involved in glycogen breakdown (glycogenolysis) and enzymes that convert glucose to ATP (glycolysis). This action shifts muscle from aerobic to anaerobic metabolism and reduces the rate at which the body uses up ATP and phosphocreatine. This means more energy is available to the muscles for longer periods of time.
Reduces Ammonia and Prevents Muscle Burnout
Ammonia acts as a signal for muscle fatigue by inhibiting the conversion of pyruvate to acetyl-CoA, and this blocks muscle contraction. Citrulline buffers ammonia via the urea cycle and increases ornithine levels. It promotes ureogenesis (production of urea) and bicarbonate resorption, which allows it to perform its buffering action against ammonia.
Reduces Post-Workout Muscle Soreness
Citrulline malate supplementation has been shown to reduce post-workout muscle soreness for up to 48 hours in trained athletes and also reduce the sensation and onset of muscle fatigue.
Helps Increase NO Production
Citrulline increases plasma levels of L-arginine in a dose-dependent matter. It has been shown that supplementing with citrulline can increase the levels of L-arginine, for more availability for the NOS pathway of NO production. More NO means greater blood flow and better nutrient delivery to working muscles.
Helps Restore Protein Synthesis
Citrulline can even help restore muscle protein synthesis rates and muscular function by improving nitrogen balance and encouraging use of amino acids (such as BCAAs) in muscles during exercise. Improved nitrogen retention and the presence of BCAAs help signal the mTOR pathway of protein synthesis.