By Dominic E. 
Introduction to Natural Performance Enhancement
Athletes and fitness enthusiasts are continuously seeking natural ways to enhance performance, endurance, and recovery. Among the countless supplements available, nitric oxide (NO) boosters like beetroot and L-citrulline stand out for their scientifically proven benefits. Nitric oxide, a naturally occurring molecule in the body, plays a critical role in improving blood flow and oxygen delivery—two essential factors for peak athletic performance.
Beetroot and L-citrulline have emerged as powerhouse supplements, praised for their ability to elevate NO levels. Beetroot, rich in dietary nitrates, supports NO production, reducing the oxygen cost of exercise and improving endurance. L-citrulline, an amino acid, converts into L-arginine in the body, further enhancing NO synthesis and aiding muscle recovery. Together, these compounds provide a synergistic boost for athletes at all levels. In this article, we explore the science behind these supplements, their impact on athletic performance, and how to incorporate them effectively into your fitness regimen.
Scientific Evidence and Research Findings
Research underscores the efficacy of beetroot and L-citrulline in enhancing various aspects of physical performance:
Beetroot and endurance performance improvements: A 2017 meta-analysis published in Frontiers in Physiology highlighted that beetroot juice supplementation significantly improved endurance and reduced the oxygen cost of exercise in athletes. By enhancing mitochondrial efficiency and reducing fatigue, beetroot enables athletes to perform longer at higher intensities (Jones et al., 2017).
Power Output: A 2018 study in Journal of Applied Physiology found that beetroot juice supplementation increased peak power output in cyclists. The study attributed this improvement to the enhanced delivery of oxygen and nutrients to working muscles (Wylie et al., 2018).
L-Citrulline and post-exercise recovery: A 2018 study in Nutrients demonstrated that L-citrulline supplementation reduced muscle soreness by 40% post-exercise. This effect was linked to increased NO production, which improved blood flow and facilitated the removal of metabolic waste products (Pérez-Guisado et al., 2018).
Strength and Power: Research published in the Journal of Strength and Conditioning Research in 2020 revealed that L-citrulline enhanced peak strength during resistance training. This was attributed to its ability to promote muscle oxygenation and reduce fatigue during high-intensity efforts (Matsumura et al., 2020).
Synergy of Beetroot and L-Citrulline: A 2020 study in Journal of the International Society of Sports Nutrition emphasized the amplified effects of combining beetroot and L-citrulline. Participants who used both supplements experienced improved time-to-exhaustion and reduced perceived exertion during endurance activities (Bailey et al., 2020).
Implementation Strategies and Guidelines
To maximize the benefits of beetroot and L-citrulline for athletic performance, consider the following strategies:
Beetroot:
Optimal beetroot supplementation dosage and timing: Consume 6–8 ounces of beetroot juice or 300–500 mg of beetroot powder daily. For athletic events, begin supplementation 3–5 days before the event for optimal nitrate loading. Take beetroot 2–3 hours before exercise to allow sufficient time for nitrate conversion to NO. Fresh beet juice, powders, or capsules are effective options. Ensure the product specifies nitrate content.
L-Citrulline:
L-citrulline dosage for endurance and strength training: For endurance and strength training, 6–8 grams of L-citrulline malate is effective. Split the dosage into two servings if gastrointestinal discomfort occurs. Consume L-citrulline 30–60 minutes before workouts for immediate effects on blood flow and endurance.
Combining Both:
Combining beetroot and L-citrulline enhances NO production synergistically. Use them together before high-intensity workouts for enhanced performance benefits.
Hydration and Nutrition:
Stay hydrated to support optimal blood flow and nutrient absorption. Pair these supplements with a balanced diet rich in antioxidants for enhanced supplement effectiveness.
Safety Considerations
While beetroot and L-citrulline are generally well-tolerated, certain considerations are essential:
Beetroot may cause harmless discoloration of urine or stool (beeturia). L-citrulline can cause mild gastrointestinal discomfort at high doses. Start with a lower dose to assess tolerance. Always consult a healthcare provider before starting any supplement, particularly if you have underlying health conditions or are taking medications.
Final Insights
For athletes and fitness enthusiasts, beetroot and L-citrulline offer a natural, effective way to elevate performance, endurance, and recovery. By leveraging their ability to boost nitric oxide levels, these supplements enhance oxygen delivery, reduce fatigue, and support muscle recovery—critical factors for excelling in any sport or physical activity. The science is clear: incorporating beetroot and L-citrulline into your routine can take your training and competition results to the next level. Whether you’re aiming for a personal best or recovering faster from intense sessions, these NO boosters provide the competitive edge for achieving athletic goals.
Research Citations
Jones, A. M., et al. (2017). “Dietary nitrate and physical performance.” Frontiers in Physiology. [Link]
Wylie, L. J., et al. (2018). “Beetroot juice and peak power output.” Journal of Applied Physiology. [Link]
Pérez-Guisado, J., et al. (2018). “Effects of L-citrulline supplementation on muscle soreness and recovery.” Nutrients. [Link]
Matsumura, Y., et al. (2020). “L-citrulline improves resistance training performance.” Journal of Strength and Conditioning Research. [Link]
Bailey, S. J., et al. (2020). “The synergistic effect of beetroot and L-citrulline supplementation on exercise performance.” Journal of the International Society of Sports Nutrition. [Link]