Protein or BCAAs ??

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Protein or BCAAs ??

Post by Kev » Sat Mar 10, 2012 9:18 pm

All about the protein
Protein supplements have become the most popular macronutrient supplement especially in the fitness and health industry. Important functions of these supplements are that they promote positive nitrogen balance, thus providing an anabolic state for the growth and repair of muscles from strenuous and prolonged exercise. Protein sources rich in branched chained amino acids (BCAAs) are higher quality as they increase muscle protein synthesis (MPS) and attenuate the breakdown of muscle from strenuous workouts. Modern technology has enabled us to obtain high-quality protein from vegetable and animal sources, mainly soy and whey protein isolates. There is ongoing debate whether more protein is good, or whether selective consumption of the BCAAs is more effective.

Soy protein
Soy is known to have a high concentration of BCAAs and health-beneficial anti-oxidants (isoflavones) which lower bad (LDL) cholesterol. There is insufficient evidence to support the added health benefits of soy protein supplements as they are usually the most refined form (soy protein isolate). It is also common misconception among bodybuilders that soy protein is unfavourable, as it is does not reduce testosterone levels or produce changes in lean mass.

Whey is the single most consumed and popular nutritional supplement given the high concentrations and bio-availability of BCAAs and essential amino acids (EAAs) compared to vegetable proteins. Additionally, whey proteins also have cysteine and methionine which can be converted to glutathione, an antioxidant.
Common forms of whey are whey protein isolate (WPI) and whey protein concentrate (WPC). WPI is absorbed most effectively, whilst WPC contains a higher fraction of glycomacropeptide (GMP) which contains casein, thus providing a gradual release post-consumption. Hydrolysed whey reduces the risk of allergy to milk proteins. One study has shown that WPI can accelerate muscle strength recovery after a single workout session. Additionally it is observed that consumption of whey protein post-workout is effective in promoting a positive nitrogen balance conducive for MPS leading to hypertrophy (growth in size) overtime.
Most commercial supplements may also promote whey components such as alpha-lactalbumin, beta-lactoglobulin or GMP which are all important bio-available sources of EAAs including BCAAs. Another component of whey protein is lactoferrin, though in low quantities in commercial whey has antioxidant and antibacterial properties thus aiding immune function.

Are BCAAs a smarter alternative ?
Among the 8 EAAs required by humans for optimal health, the BCAAs consist of isoleucine, valine and leucine, a key amino acid in MPS. Generally, excess BCAAs are toxic to the body. However, during exercise and training, oxidation of BCAAs increases in skeletal muscle and its metabolites can be used to attenuate exercise-induced muscle damage, increase MPS and in energy production pathways (refer to ATP). One study showed that supplementation with BCAAs is able to reduce cortisol (increases fat stores, also used as marker of catabolism) significantly in response to intense training and increasing testosterone (marker of anabolism) levels. Small amounts of BCAAs before training can help prevent delayed onset muscle soreness (DOMS). Thus, the aim is to create an anabolic hormonal profile whilst reducing muscle fatigability. This is also beneficial to athletes in adapting to new training skills or regimes.

BCAAs are gaining popularity and are purportedly more ergogenic (performance-enhancing) than protein. The effectiveness of supplementation with BCAAs only, depends on each individual’s lean mass and physiological variations such as muscle oxidation of BCAA and larger physiques would have to consume more for adequate muscle uptake. It should be noted that athletes and professional bodybuilders receive professional nutritional counselling which aids in optimizing the right amount of supplement to consume to maintain an anabolic profile.
Take what works best

Given the vast differences in workout regimes, constitutional profile and existing research, it is still too early to take sides on which supplement works best. Timing is important, as BCAAs or WPIs are best consumed before and immediately following workouts. Currently, whey protein has been shown to be most effective at promoting growth in lean mass whilst BCAA is effective in promoting muscle growth, repair and endurance to weight training.


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