Citrulline malate is a compound often overshadowed by more well-known ingredients in athletic-performance supplements. Proponents of its use consider it to be an overlooked compound with beneficial effects.
But what can this ingredient do for you? Let’s take a closer look at the studies to find out.
Increase ATP Production and Reduce Muscle Fatigue
Citrulline malate is shown to enhance athletic anaerobic performance.
In one randomized, double-blind study, 41 men performed 2 consecutive flat barbell bench exercises, 16 sets in total. Each subject performed the exercises, once with 8 g citrulline malate and the other with a placebo. Researchers evaluated subjects’ resistance using fatigue tests and discovered test subjects’ reps per set increased with citrulline malate supplementation. Additionally, research reveals subjects experienced significantly lower levels of muscle soreness after using citrulline malate.
Another study lasting 15 days shows daily doses of 6 g citrulline malate during rest-exercise-recovery protocols in men increased the rate of oxidative ATP production by 34%. Along with increased energy, the subjects also experienced a reduction in fatigue and a 20% increase in phosphocreatine recovery rate post-exercise.
Enhance Amino Acid Utilization
Clinical studies show citrulline malate enhances amino acid utilization during exercise.
Seventeen pre-professional cyclists volunteered for a study in which they were randomly assigned to either ingest 6 g citrulline malate or a control, 2 hours prior to exercise. Blood samples were taken twice, 15 minutes and 3 hours after the race. Data reveals essential amino acid plasma-concentration decreased, but there was a significant increase in non-essential amino acid concentration. Researchers explain citrulline malate supplementation optimizes branched chain amino acid utilization during exercise.
This is important because branched chain amino acids are metabolized in the muscle instead of the liver, providing additional energy sources during exercise.
Protect Against Ammonia
Excessive ammonia amounts in the blood cause muscle weakness, fatigue, and even liver and kidney damage.
Although critiqued by NYU Langone Medical Center for being below the level of modern scientific standards, one study shows promising results that citrulline malate combats ammonia damage to muscle cells.
The same study also suggests citrulline malate may favor bicarbonate renal (kidney) reabsorption, protecting against acid build up which causes muscle fatigue.
Treat Fasting-Induced Muscle Cell Atrophy
Preliminary research suggests citrulline may beneficially affect skeletal muscle-cell wasting and weakness, potentially through calcineurin signaling.
During a study, cells were fixed and stained. Myotube diameters –embryonic progenitor cells that result in muscle cells – were either incubated with 2.5 mm alanine (control) or with amino acids like citrulline. Results show some myotube’s formation was increased by 50% when incubated with citrulline compared to the control. Researchers attribute this muscle cell differentiation to increased mRNA expression by signaling calcineurin-A (protein phosphate) expression.
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