Please ensure Javascript is enabled for purposes of website accessibility Best Post-Workout Nutrients: Research Update

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science nutrition <strong>blog</strong>

 By Steve Blechman


A study published March 22, 2022, in the Journal of the International Society of Sports Nutrition “examined the effects of short term betaine supplementation and muscle endurance, plasma lactate, testosterone and cortisol levels, and the testosterone to cortisol T/C ratio in response to acute resistance exercise (RE).”

It was a double-blind crossover study with 10 adolescent male handball players who consumed either placebo (maltodextrin) or betaine (2.5 grams) daily for two weeks taken after meals. “Betaine powder and maltodextrin were identical in appearance and taste and were not distinguishable by the participants or investigators.”

“Betaine supplementations enabled participants to perform more repetitions during the bench press and leg press and also reduced post exercise lactate concentration. We also observed that betaine amplified the testosterone responses and dampened the cortisol response to a single session of RE compared to placebo. Moreover, in comparison to baseline values betaine supplementations led to an increase in resting testosterone and T/C ratio,” researchers said.

The researchers reported “short term betaine supplementations significantly changed the indices of endocrine function in adolescent males. To the best of our knowledge, this was the first study to investigate the interaction between betaine supplementation and the acute steroid hormone response to RE. We observed that betaine administration for 14 days resulted in significant increase in plasma testosterone responses,” after a bout of high intensity resistance training.


Betaine, also known as trimethylglycine, is a natural osmolyte like creatine. It is important in maintaining cellular hydration. As an osmolyte, betaine enhances muscle cell swelling, stimulating protein synthesis and decreasing protein breakdown, resulting in muscle growth. Betaine also has been shown to increase growth hormone and insulin-like growth factor 1 (IGF-1). Betaine supplementation (2.5 grams) reduced fatigue and increased power and strength after 15 days of high-intensity, high-volume bench press and squat training. Natural betaine, also at 2.5 grams per day, improved arm muscle size and increased body composition – increasing lean body mass and lowering body fat. Other studies have shown 7.8 percent rise in IGF-1 levels and a 6.1 percent drop in the muscle catabolic hormone cortisol. Taken together, betaine is an excellent post-workout supplement when combined with leucine and creatine. For further muscle growth benefits, take the electrolytes potassium and magnesium citrate post-exercise. Potassium and magnesium citrate enhance hydration and muscle cell volume as an osmolyte, working synergistically with creatine and betaine to enhance muscular recovery and muscle growth. Potassium citrate is also an acid buffer. High-protein, low-carbohydrate diets result in low-grade, chronic acidosis, enhancing muscle breakdown and muscle wasting. Potassium and magnesium citrate can buffer acidosis and preserve muscle mass when following a high-protein, acid-forming diet.


Creatine is an extremely popular sports supplement that increases strength, power and lean muscle mass. Creatine monohydrate is the gold standard and most researched form of creatine. In 1992, as Twinlab’s Vice President of Product Development and Marketing (1974-2001), I was the first to bring to the retail market creatine monohydrate (as Creatine Fuel). While there are several different forms of creatine available today, creatine monohydrate has been shown to be the most cost-effective! Creatine increases power output during high-intensity sprints and improves endurance capacity by allowing athletes to exercise at a faster pace. Creatine also promotes muscle adaptations to training and stimulates muscle growth. Creatine can stimulate muscle growth by enhancing IGF-1, muscle cell formation and increasing protein synthesis. Creatine can also inhibit the production of the muscle-wasting protein myostatin. Myostatin acts by inhibiting the growth of muscles – it prevents them from growing too large. By inhibiting myostatin, creatine can promote the growth of skeletal muscle. The blockade of myostatin has the potential as a treatment for various muscle-wasting disorders such as sarcopenia and loss of muscle during aging. Research has shown that creatine monohydrate combined with leucine can reduce the negative effect of myostatin and enhance muscle growth. So, it makes scientific sense to combine leucine with creatine monohydrate to maximize recovery, protein synthesis and muscle growth.


Leucine promotes recovery by stimulating the mTOR pathway to increase protein synthesis to repair injured tissue. Leucine, one of the branched-chain amino acids (BCAAs), is the most important chemical that turns on the mTOR pathway, so it is likely that consuming leucine after exercise would be more effective (and cheaper) than consuming BCAAs. The addition of isoleucine and valine may hinder the benefits of leucine due to competition for transport into muscle cells. The BCAAs share the same active transport system into cells and muscle cells. Indeed, isoleucine and valine have been shown to inhibit absorption of leucine. In the March 2018 issue of the International Journal of Sports Nutrition and Exercise Metabolism, it was reported that men fed 6 grams of whey protein supplemented with leucine, isoleucine and valine observed less protein synthesis than whey protein supplemented with just leucine. Also, research has shown that valine can cause insulin resistance in muscle, which is detrimental to muscle growth and enhances the accumulation of body fat. Also, many athletes consume glutamine supplements because they may boost the immune system. A Belgium study, however, found that glutamine suppresses the mTOR pathway and could interfere with muscle protein synthesis. Yes, glutamine is antagonistic to leucine when it comes to turning on protein synthesis! A dipeptide of alanine and glutamine called Sustamine also fails to turn on mTOR. The science supporting glutamine as a muscle-building, performance-enhancing supplement is quite lacking.

Advanced Molecular Labs (AML) Post Workout for Enhanced Exercise Performance and Recovery

For maximum benefits, take 1 scoop of AML Post Workout immediately after a resistance-training workout before eating a post-workout meal. When taking AML Post Workout you will have support for improved muscle growth from multiple pathways and faster recovery time after your workout.

To enhance muscle performance and recovery after high-intensity exercise, take post workout nutrients such as leucine (5 grams), creatine monohydrate (5 grams) and betaine (2.5 grams) as present in AML Post Workout before a post-workout meal.


©Published by Advanced Research Media, Inc. 2022

©Reprinted with permission from Advanced Research Media, Inc.




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