When it comes to improving your athletic performance, there are really only three variables you can control; strength, endurance, and recovery. Citrulline Malate is a synergistic combination of the nonessential amino acid L-Citrulline and Malic Acid. Studies suggest that Citrulline Malate is a powerhouse ergogenic aid, with results showing that it can benefit and enhance all three of these crucial variables. If you want to improve your strength gains, boost endurance, and recover faster and cut down on muscle soreness, Citrulline Malate is exactly what you may need.
In this ultimate guide to citrulline malate supplementation, you will learn
- What Is Citrulline Malate?
- What Does Citrulline Malate Do?
- How Does Citrulline Malate Work?
- What Are The Benefits Of Citrulline Malate?
- L-Citrulline Vs Citrulline Malate
- Arginine Vs Citrulline Malate
- Citrulline Malate Dosage
- When Should You Take Citrulline Malate?
- What Are The Side Effects Of Citrulline Malate?
- What’s The Best Citrulline Malate Supplement?
What Is Citrulline Malate?
Often found as an active key ingredient in a majority of pre-workout supplements, L-Citrulline is a nonessential amino acid that helps promote the natural release of nitric oxide (NO). NO is a vasodilator, meaning it widens blood vessels, which opens the flood gates for more oxygen and blood flow to be transported to your muscle tissue. This is why L-citrulline or other known NO boosters such as L-arginine and beet juice, are marketed for their infamous “pump”. Extracted from apples, malate is a derivative of malic acid and contributes to the sour taste of fruits. When these two constituents are combined, they create Citrulline Malate. Studies have shown that Malate is the active key ingredient, that contributes to added performance benefits of Citrulline Malate, as opposed to L-citrulline alone.
Citrulline Malate has been used for over 25 years in Europe as a pharmacological treatment for fatigue, muscle weakness, and dementia. Studies have shown that citrulline malate supplementation helps improve muscle performance in subjects suffering from asthenia (abnormal physical weakness or lack of energy). Only recently, has Citrulline Malate been offered for commercial use in sports supplementation due to its proven effectiveness on performance measures and outcomes.
What Does Citrulline Malate Do?
Citrulline Malate enables the natural production of nitric oxide. Nitric oxide is a gas that's main purpose is to promote vasodilation or increased blood flow.
NO is one of the most fundamental molecules of the body’s vasculature, regulating key signaling pathways and nutrient transport. NO is secreted by the endothelial cells and line the inner walls of your blood vessels, communicating to your smooth muscle cells to relax, through vasodilation. Consequently, nitric oxide widens blood vessels increasing blood flow and circulation without increasing blood pressure. Research has shown that nitric oxide is essential for overall health, especially cardiovascular health as it supports the transport of blood, oxygen, and nutrients to your body and muscle tissue efficiently and effectively.
RELATED ARTICLE What Are Nitric Oxide (NO) Boosters
Through this transport, studies have shown benefits of Nitric Oxide used as an ergogenic aid, specifically helping
- Improve Recovery Time
- Increase Strength
- Fuel Endurance
- Delay Muscle Fatigue
Nitric Oxide aside, Citrulline Malate is unique as compared to other NO boosters, in that it works in many fascinating ways, due to the addition of malate. Malate which is an intermediate of the tricarboxylic acid cycle (TCA) or urea cycle affects aerobic ATP production through anaplerotic reactions [R]. Therefore, Citrulline Malate has added benefits such as
- Delayed Muscle Fatigue- Increases ATP Production [R]
- More Power- Increases phosphocreatine levels [R]
- Increased Strength- Facilitates Muscle Protein Synthesis [R]
- Better Recovery- Enhances Amino Acid Utilization [R]
How Does Citrulline Malate Work?
L-Citrulline is a key component in what’s called the urea cycle. The urea cycle facilitates the detoxification of ammonia into urea, which is the metabolic waste product of protein digestion generated from exercise. When your digestive system metabolizes Citrulline Malate, enzymes in your liver convert it into ornithine and arginine, where it is then converted into Nitric Oxide (NO).Higher ornithine and arginine plasma content improves the ammonia recycling process and nitric oxide metabolism. Interestingly, research indicates that citrulline supplementation is more efficient in raising plasma nitric oxide content, than supplementing arginine alone.
Lactic acid buildup is an essential component of muscle fatigue. Several studies have shown the close connection between the accumulation of ammonia in the blood and the deterrence of cellular energetic processes. NO, regulates many of the physiological functions of skeletal muscle in connection with these processes. Citrulline Malate supplementation as a performance-enhancing product has been based upon three distinct mechanisms of action.
L-Citrulline Facilitates Clearance Of Ammonia via the Urea Cycle
With excess availability of l-citrulline, acceleration of the urea cycle occurs, facilitating the clearance of ammonium. Ammonium is a critical factor in fatigue, because its intracellular accumulation stimulates glycolysis, while blocking the aerobic utilization of pyruvate. This results in a deviation of energy metabolism toward the exclusive formation of lactate [R].
Malate Is An Intermediate Of The Krebs Cycle
Malate is an intermediate of the Krebs cycle, and behaves as a metabolic shuttle between mitochondria and cytoplasm, bypassing the blockade produces by ammonium and limits the accumulation of lactic acid [R].
NO Regulates Uptake
Of course, we can’t forget about the vasodilation effects of NO and the crucial role it plays in nutrient, oxygen, and blood uptake direct to skeletal muscle tissue.
What Are The Benefits Of Citrulline Malate?
Science aside, Citrulline Malate may be the most impressive sports supplement when it comes to overall improvements in athletic performance and training. Numerous studies have shown that Citrulline Malate can delay muscle fatigue, increase strength, and optimize exercise-induced muscle recovery. Imagine if you could perform an entire workout and reduce muscle fatigue just by 20%. You would easily knock out more reps, optimize training times, and gain more lean muscle mass. Not to mention your muscular endurance would be at an all-time high. Let’s look at how adding Citrulline Malate into your supp lineup can benefit your performance outcomes.
Citrulline Malate Benefits: Delays Muscle Fatigue
One of the greatest benefits of Citrulline Malate is it’s proven ability to delay muscle fatigue, by promoting an increase in aerobic energy (ATP) production.
A study published in the British Journal Of Sports Medicine found that 6g of Citrulline Malate taken daily, reduced muscle fatigue, by producing a 34% increase in the rate of oxidative ATP production during exercise. The study also found a 20% increase in the rate of phosphocreatine recovery after exercise, indicating a larger contribution of oxidative ATP synthesis to energy production. [R]
Citrulline Malate Benefits: Optimizes Exercise Recovery
More oxygen and blood flow sent to the muscle tissue means optimized post-workout recovery. Moreover, citrulline malate helps enhance the use of amino acids, especially the branched-chain amino acids, which are responsible for muscle protein synthesis (the muscle-building process), which decreases muscle mass breakdown and soreness.
In a study, published in the Journal Of Strength and Conditioning Research, 41 study participants performed two consecutive flat barbell bench-training sessions for a total of sixteen sets. 8g of Citrulline Malate was administered during one of the first two sets and placebo was administered for the third. The subjects' resistance was tested using the repetitions to fatigue test at 80% of their predetermined one rep max in the 8 sets of bench presses during the training session. The number of reps showed a significant increase from placebo treatment to treatment with Citrulline Malate from the third set achieving 52.92% more repetitions. The study also showed a 40% reduction in muscle soreness at 24 hours and 48 hours with a response rate greater than 90% with Citrulline Malate supplementation. [R]
Citrulline Malate Benefits: Increases Strength
Citrulline Malate stimulates muscle protein synthesis (MPS). MPS is the biological process of increasing muscle mass, where cells generate new proteins [R]. Translation, MPS is responsible for muscle growth, accelerated muscle recovery and improved muscle endurance.
In a randomized double-blind control study published in the European Journal Of Sports Science 17 female tennis players consumed 8g of Citrulline Malate or placebo one hour before training. The results indicated that the citrulline group exhibited greater maximal strength, with significant increases in peak and explosive power [R].
L-Citrulline Vs. Citrulline Malate
In the past decade, there have been numerous studies that have investigated the effects of l-citrulline on strength and power.
Although research has shown a positive effect on athletic performance with Citrulline Malate, studies have had very mixed and inconclusive results with L-Citrulline supplementation alone. L-Citrulline is the free form version of the amino acid citrulline. Citrulline is converted into arginine and nitric oxide, which provides for more blood and oxygen transport.
Studies indicate that the surmounting difference between L-Citrulline vs Citrulline malate is that L-citrulline alone does not directly affect aerobic ATP production. Malate which is an intermediate of the tricarboxylic acid cycle (TCA) or urea cycle affects aerobic ATP production through anaplerotic reactions [R].
A systematic review published in Sports Medicine performed a comprehensive analysis of clinical research regarding l-citrulline supplementation and it’s affect on performance outcomes specifically strength and power. The inclusion criteria of the review, included strength and power variables from performance tests involving multiple repetitive muscle actions of large muscle groups, consisting of either resistance training sets or sprints lasting 30 s or less. Tests involving isolated actions of small muscle groups or isolated attempts of single-jump tasks were not included for analysis due to differences in metabolic requirements. Studies were excluded from consideration if they lacked a placebo condition for comparison, were carried out in clinical populations, provided a citrulline dose of less than 3 g, provided the citrulline dose less than 30 min prior to exercise testing, or combined the citrulline ingredient with creatine, caffeine, nitrate, or other ergogenic ingredients.
The review identified 12 studies consisting of 198 participants, which met the inclusion criteria. The results showed that L-Citrulline effects were so small, that they were considered null. However, the results may be beneficial to very high-level elite athletes, in which competitive outcomes are decided my diminutive margins. Further research is needed to determine whether or not the supplementation of L-Citrulline alone provides any real performance benefits or outcomes [R].
L-Arginine Vs. Citrulline Malate
Arginine, specifically arginine alpha-ketoglutarate, was what started the NO supplement craze back in the late 1990s, because arginine is converted into Nitric Oxide. So why should you supplement with Citrulline Malate instead of arginine? Both Citrulline Malate and Arginine produce greater blood flow to muscle fibers, by relaxing the blood vessels, allowing them to widen and dilate. More oxygen and nutrient transport directly translates into more energy and endurance. However, studies have shown that Citrulline Malate is a far superior nitric oxide booster than arginine.
Arginine undergoes what’s called first-pass metabolism (FPM) and is metabolized by the gastrointestinal tract (GI) and liver. Studies show that 70% is extracted while being metabolized. Additionally, the 30% that does escape failed to increase higher flux concentrations of arginine to promote the release of NO. Unlike arginine, Citrulline Malate does not undergo FPM and bypasses metabolic processing through the gut and liver. Therefore, Citrulline Malate is more efficient than arginine in facilitating nitric oxide production [R]. Therefore supplementing with Citrulline Malate is by far more efficient and effective in increasing arginine than arginine supplementation. This is due to the fact that the only known fate of citrulline is its conversion into arginine and because citrulline losses in the urine are minimal [R].
Citrulline Malate Dosage?
According to the studies, a dosage of 5-8g should be taken 20-30 minutes pre-workout or prior to training.
When Should You Take Citrulline Malate?
Citrulline Malate should be supplemented on training days, 20-30 minutes pre-workout. Citrulline Malate does not need to be dosed, cycled, or loaded on non-training days.
What's The Best Citrulline Malate Supplement?
Unlike other pre-workout supplements that under-dose their ingredients Swolverine's Citrulline Malate offers 5g per serving with 100 unflavored servings per bottle. Citrulline Malate naturally promotes the production of nitric oxide (NO), which supports greater endurance, muscle force, power, and delays muscle fatigue* Citrulline Malate is proven to help promote strength, improve endurance, and optimize muscle recovery.
What Are The Side Effects Of Citrulline Malate?
According to the Food and Drug Administration (FDA), Citrulline Malate has shown no adverse effects, as reported in any pharmacokinetic study.
Ultimate Guide to Citrulline Malate: Takeaway
The clinical evidence suggests that Citrulline Malate proves to be, not only a good nitric oxide booster for but the best no booster for endurance athletes. Through its ability to increase strength, enhance endurance, and optimize post-workout recovery and soreness, there's never been a better supplement to help in every aspect of your training. If you want to gain an athletic edge over your competition, lift heavier, clock faster times, and train harder with less muscle fatigue and soreness then you should absolutely add Citrulline Malate to your pre-workout regimen. By adding Citrulline Malate into your workout routine, you will get to your goals faster and achieve greater enhancements in overall performance.
Looking To Add Citrulline Malate To Your Supplement Regimen To Crush Your Workout Performance?
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