BCAAs alone, not sufficient for maximal muscle growth

For body builders, supplements containing amino acids are considered to be an important part of the nutrition plan. From improving brain function to boosting muscle strength — lifting heavy weights has many benefits. Those who lift weights might be familiar with Branch Chain Amino Acids (BCAAs). They are extremely popular within the fitness industry. However, a recent research suggests the popular muscle building supplements are ineffective when taken in isolation. The study shows that while BCAA supplements do stimulate the muscle building response in individuals after they lift weights, other muscle-building supplements are far more effective. Other supplements that contain all necessary amino acids stimulate a greater muscle growth response, which suggests that taking BCAA supplements alone is not the best way to optimise muscle growth with weight training. The scientists also investigated how effective the supplements were at stimulating the machinery inside the muscle itself that leads to muscle growth. They found that while BCAA drinks stimulate the body’s muscle building systems, they lack some essential amino acids that are necessary to support a maximal muscle growth response.

Professor Kevin Tipton, Chair in Sport, Health and Exercise Sciences at the University of Stirling, said: “Amino acids are the building blocks of proteins and the special class of amino acids, known as BCAA, stimulate the muscle growth response. These supplements are considered to be an important part of the nutrition plan for many body builders, weightlifters and others seeking muscle growth. Our results show that the common practice of taking BCAA supplements in isolation will stimulate muscle protein synthesis — the metabolic mechanism that leads to muscle growth — but the total response will not be maximal because BCAA supplements do not provide other amino acids essential for the best response.”

He added, “A sufficient amount of the full complement of amino acids is necessary for maximum muscle building following exercise. Athletes interested in enhancing muscle growth with training should not rely on these BCAA supplements alone.”