Please ensure Javascript is enabled for purposes of website accessibility MIRACLE POWERS OF LEUCINE: New Study Says It Boosts Muscle & Strength

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science nutrition <strong>blog</strong>

By Steve Blechman


An amazing new study recently appeared in the January 21, 2020 Journal of Nutrition that found that feeding cerebral palsy (CP) adolescents and adults pure leucine and essential amino acid for 10 weeks boosted muscle and strength! After 10 weeks of pure leucine feeding dissolved in water, there was a 25.4% increase in muscle strength and 3.6% increase in muscle volume in the leucine group, with no changes in the control group.          

This was accompanied by a 59.1% reduction in C-Reactive protein (a measurement of systemic inflammation) and improved perceptions of well-being in the leucine group. The conclusion of this study was, “Improvements in muscle strength and volume with leucine supplementation might provide important functional changes for adults with CP and could be partly explained by reduced inflammation. The improved well-being highlights its capacity to improve the quality of daily living.” The improvement of muscle strength and volume of skeletal muscle with supplemental leucine of cerebral palsy adolescents and adults can provide improvement in strength and power to grasp, reach, balance, lift, and walk and lower inflammation, provide better metabolic health, blood sugar control, prevention of cardiovascular disease and premature death.

Cerebral palsy is a debilitating congenital neurological disorder that is due to abnormal brain development or injury, often before birth that affects body movements, muscle tone, muscle coordination, balance, strength and posture. It is rare and affects 200,000 cases in the United States per year.  Symptoms include rigid limbs and involuntary motions. Treatment includes occupational and special physical therapy, exercise, drugs and sometimes surgery. A person with cerebral palsy might need special equipment to walk, or might not be able to walk at all, and might need lifelong care. Currently, there is no cure for cerebral palsy and hopefully with ongoing research a cure will be found.           

Over the last couple of years, I have been a big proponent of the essential amino acid leucine for activating the anabolic trigger of protein synthesis in muscle over branched-chain amino acid mixtures containing leucine, isoleucine and valine (BCAAs). Branched-chain amino acid mixtures (BCAAs) refer to three amino acids: leucine, valine and isoleucine. Over the years, the popularity of BCAA mixtures has grown with the false understanding that BCAAs alone are most effective for increasing the anabolic drive in muscle protein synthesis. The research has shown that taking pure leucine is more effective than the combination of BCAAs (leucine, isoleucine and valine). Research has also shown that leucine alone (not isoleucine and valine) is anabolic, and enhances protein synthesis (Journal of Physiology, 2013). Research has demonstrated that isoleucine and valine limit the effectiveness of leucine when taken together! Isoleucine and valine compete for absorption into the blood and into muscle cells. All three BCAAs share the active transport system. Research in humans has shown that taking BCAAs (leucine, isoleucine, valine) together can decrease muscle protein synthesis. That’s why I recommend leucine by itself over BCAA mixtures because combining BCAAs might limit the stimulation of protein synthesis because of reduced uptake of leucine in the blood and in muscle cells. Leucine (5 grams) should be taken preferably post-workout 30-60 minutes before a post-workout meal to activate the anabolic trigger of protein synthesis. Research has shown that pure leucine is more anabolic than the same amount of leucine in food. A Japanese study published on October 18, 2018 in the journal Nutrients found that taking leucine supplements alone may be better for muscle protein synthesis and more anabolic than leucine from food! Japanese researchers found that blood levels of leucine were higher from pure, free leucine taken alone compared to the same amount of leucine in a meal. Increase in muscle protein synthesis is dependent on leucine concentration. Research has shown that leucine stimulates the anabolic effect of muscle protein on its own (Wilkinson et al., J Physiol 2013). The Nutrients study stated that, “based on these findings, it is presumed that compared to the intake of protein alone or free amino acids alone, the intake of dietary protein from mixed meals may result in a lower maximum plasma leucine concentration.” However, no study to date has investigated the changes in amino acid concentrations after the ingestion of mixed meals in comparison to those after the intake of a similar amount of free amino acids (Nutrients, October 2018). The post- workout meal will provide all the essential amino acids for optimal muscle protein synthesis.

A most recent review on branched-chain amino acid intake and muscle protein synthesis in humans was published September 2019 in the journal Einstein. This is a terrific updated review! The review acknowledges that, “leucine alone is able to induce a muscle protein synthesis response via activation of the mechanistic target of rapamycin complex 1 (mTOR1), a vital cell growth regulator.” 

Benefits of Leucine:

-Leucine is the key anabolic trigger to protein synthesis.

-Increases in muscle protein synthesis are dependent on leucine concentration.

-5 grams of leucine can increase the anabolic effects of protein synthesis when eating less protein, which is ideal on a ketogenic diet.

-Research has shown 6.25 grams of whey protein with 5 grams of leucine is equivalent to at least 25 grams of whey protein.

-Anabolic resistance in people over 40 can be overcome by consuming greater quantities of leucine.

-Leucine and not total protein content of a supplement is the primary determinant of muscle protein anabolic responses in healthy older people.

-Research has shown that pure leucine is more anabolic than protein in food!

-Leucine is the key amino acid for enhancing mTOR pathway that regulates cell growth and protein synthesis.

-Leucine has many benefits: powering muscle growth, preventing muscle loss and enhancing recovery.

ADVANCED MOLECULAR LABS (AML)™ POST WORKOUT CONTAINS: 5 grams of pure leucine plus 5 gram of creatine monohydrate and 2.5grams of betaine. Leucine is a potent mTOR activator and creatine functions as a myostatin inhibitor. Betaine stimulates growth hormone (GH) and insulin-like growth factor-1 (IGF-1) secretion. Combining leucine with creatine monohydrate and betaine supports muscle growth from multiple pathways, helping you recover faster and grow more lean muscle.

For best results as recovery after exercise, take ADVANCED MOLECULAR LABS (AML)™ POST WORKOUT which contains 5 grams of leucine (on an empty stomach) 15-30 minutes before a post-workout meal. By taking pure leucine on an empty stomach, you will get a better spike in blood levels than if you take leucine with food, because food can slow leucine’s absorption. When leucine is taken on an empty stomach, it’s a powerful metabolic switch that turns on protein synthesis. Leucine increases mTOR activity for several hours after training. When leucine is taken after resistance exercise, and before a post-workout protein-containing meal rich in essential amino acids, that’s also found in ADVANCED MOLECULAR LABS (AML)™ POST WORKOUT®, it will trigger greater protein synthesis for improved recovery and greater gains!



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