BODY SHOP: Training, Nutrition and Supps Research
If there were an easy way to add a muscle-building boost to your postworkout protein shake, would you be interested? Of course, you would. Well, that muscle-boosting ingredient could very well be one amino acid in particular: leucine.
Protein makes up approximately 80 percent of the dry weight of skeletal muscle, and muscle cells need a plentiful and constant supply of amino acids for renewal, repair and synthesis of new proteins. Whey is a highly bioavailable protein source that contains an abundance of the branchedchain amino acids (leucine, isoleucine and valine), which are vital for muscle growth, especially when consumed around workouts.
Leucine makes up only 5 to 10 percent of proteins, and blood leucine levels are known to decline by about 30 percent during strength training and 11 percent to 33 percent during fat-burning cardio sessions (i.e., aerobic exercise). Thus, it makes sense that leucine requirements are much higher in athletes.
A recent study published in Biology of Sport analyzed the effects of leucine-enriched whey protein supplementation on muscle anabolic signaling in healthy, resistance-trained males. The researchers found that postworkout supplementation with leucine-enriched whey augmented intramuscular protein V\QWKHVLV VLJQLÀFDQWO\ )XUWKHUPRUH WKH\ IRXQG WKDW WKH DGGL tion of leucine to postworkout whey promoted a greater insulin response, which boosts anabolism and the shuttling of nutrients into fatigued muscle.
ACTION POINT: Although this study shows that you can boost the anabolic response to weight training with as little as 10 JUDPV RI ZKH\ IRUWLÀHG ZLWK JUDPV RI OHXFLQH ZH VXJJHVW DQ even more potent cocktail. Mix 20 to 30 grams of whey protein isolate with 10 to 15 grams of BCAAS (at a ratio of 2:1:1, leucine to isoleucine to valine) and drink it immediately postworkout. This will ensure that you have at least 10 grams of leucine on board ZKLOH DOVR UHDSLQJ WKH VFLHQFH EDFNHG EHQHÀWV RI WKH ZKH\ leucine combo.