Introduction
In the world of sports nutrition, Citrulline Malate (CitMal) has gained significant attention as a supplement that enhances performance, reduces fatigue, and boosts muscle endurance. But what does the science say? A systematic review and meta-analysis published in the International Journal of Sport Nutrition and Exercise Metabolism analyzed the effects of CitMal on strength training performance, and the results are promising.
What is Citrulline Malate?
CitMal is a combination of L-citrulline, a naturally occurring amino acid, and malate, an organic salt that plays a role in energy production. Unlike L-arginine, which is directly involved in nitric oxide (NO) production, L-citrulline bypasses liver metabolism, leading to higher plasma arginine levels and more efficient NO synthesis. This process improves blood flow, reduces muscle fatigue, and enhances endurance (Gonzalez & Trexler, 2020; Figueroa et al., 2017).
Key Findings from Scientific Research
A meta-analysis of eight placebo-controlled studies with 137 participants examined CitMal’s effects on strength training (Vårvik et al., 2021). Participants consumed 6–8g of CitMal 40–60 minutes before their workouts. The analysis revealed:
- 6.4% increase in total repetitions performed before failure (p = 0.022).
- Greater effect on lower body exercises (8.1% increase, p = 0.051) compared to upper body exercises (5.7% increase, p = 0.131).
- Small yet consistent performance benefits, particularly in multi-joint exercises.
How Does CitMal Improve Performance?
CitMal's benefits stem from its ability to increase nitric oxide production and enhance ATP (energy) production. Here’s how it works:
- Increased Blood Flow: NO-induced vasodilation delivers more oxygen and nutrients to working muscles (Bahadoran et al., 2020).
- Reduced Fatigue: L-citrulline plays a role in the urea cycle, helping buffer ammonia and delay muscle exhaustion (Rhim et al., 2020).
- Enhanced ATP Production: Malate supports the Krebs cycle, improving aerobic energy efficiency (Bendahan et al., 2002).
- Improved Recovery: Some studies suggest CitMal reduces muscle soreness post-exercise (Wax et al., 2015).
How to Use Citrulline Malate for Optimal Results
To maximize the benefits of CitMal, follow these guidelines:
- Dosage: 6–8g 40–60 minutes before training (Moinard et al., 2008).
- Timing: Peak effects occur 60–90 minutes after ingestion (Schwedhelm et al., 2008).
- Combination with Other Supplements: Works well with creatine, caffeine, and beta-alanine for enhanced performance.
Potential Side Effects and Considerations
Most studies indicate that CitMal is safe and well-tolerated, with minor side effects such as mild stomach discomfort reported in a small percentage of users (Glenn et al., 2015). Unlike stimulants such as caffeine, CitMal does not cause jitteriness or heart rate increases, making it an attractive option for those sensitive to stimulants.
Conclusion
Citrulline Malate is a promising supplement for athletes and fitness enthusiasts looking to enhance endurance, reduce fatigue, and improve training volume. While the effects may be modest, consistent use can contribute to better workout performance over time. If you’re aiming to push past training plateaus, CitMal may be a worthy addition to your supplement regimen.
References
- Bahadoran, Z., Mirmiran, P., Kashfi, K., & Ghasemi, A. (2020). Endogenous flux of nitric oxide: Citrulline is preferred to Arginine. Acta Physiologica, 231(3), e13572.
- Bendahan, D., Mattei, J.P., Ghattas, B., Confort-Gouny, S., Le Guern, M.E., & Cozzone, P.J. (2002). Citrulline/malate promotes aerobic energy production in human exercising muscle. British Journal of Sports Medicine, 36(4), 282–289.
- Figueroa, A., Wong, A., Jaime, S.J., & Gonzales, J.U. (2017). Influence of L-citrulline and watermelon supplementation on vascular function and exercise performance. Current Opinion in Clinical Nutrition and Metabolic Care, 20(1), 92–98.
- Glenn, J.M., Gray, M., Wethington, L.N., Stone, M.S., Stewart, R.W., & Moyen, N.E. (2015). Acute citrulline malate supplementation improves upper- and lower-body submaximal weightlifting exercise performance in resistance-trained females. European Journal of Nutrition, 56(2), 775–784.
- Gonzalez, A.M., & Trexler, E.T. (2020). Effects of citrulline supplementation on exercise performance in humans: A review of the current literature. Journal of Strength and Conditioning Research, 34(5), 1480–1495.
- Moinard, C., Nicolis, I., Neveux, N., Darquy, S., Bénazeth, S., & Cynober, L. (2008). Dose-ranging effects of citrulline administration on plasma amino acids and hormonal patterns in healthy subjects: The Citrudose pharmacokinetic study. British Journal of Nutrition, 99(4), 855–862.
- Rhim, H.C., Kim, S., Park, J., & Jang, K.M. (2020). Effect of citrulline on post-exercise rating of perceived exertion, muscle soreness, and blood lactate levels: A systematic review and meta-analysis. Journal of Sport and Health Science, 9(6), 1–9.
- Schwedhelm, E., Maas, R., Freese, R., Jung, D., Lukacs, Z., Jambrecina, A., & Böger, R.H. (2008). Pharmacokinetic and pharmacodynamic properties of oral L-citrulline and L-arginine: Impact on nitric oxide metabolism. British Journal of Clinical Pharmacology, 65(1), 51–59.
- Vårvik, F.T., Bjørnsen, T., & Gonzalez, A.M. (2021). Acute Effect of Citrulline Malate on Repetition Performance During Strength Training: A Systematic Review and Meta-Analysis. International Journal of Sport Nutrition and Exercise Metabolism.
- Wax, B., Kavazis, A.N., Weldon, K., & Sperlak, J. (2015). Effects of supplemental citrulline malate ingestion during repeated bouts of lower-body exercise in advanced weightlifters. Journal of Strength and Conditioning Research, 29(3), 786–792.