WHEY
Whey protein has become a staple supplement for most bodybuilders and other athletes for a good reason: it's a great protein for a wide variety of reasons.
A growing number of studies has found whey may potentially reduce cancer rates, combat HIV, improve immunity, reduce stress and lower cortisol, increase brain serotonin levels, improve liver function in those suffering from certain forms of hepatitis, reduce blood pressure, and improve performance, to name a few of its potential medical and sports related applications.
One of whey's major effects is its apparent ability to raise glutathione (GSH). The importance of GSH for the proper function of the immune system cannot be overstated. GSH is arguably the most important water-soluble antioxidant found in the body.
The concentration of intracellular GSH is directly related to lymphocytes reactivity to a challenge, which suggests intracellular GSH levels are one way to modulate immune function. GSH is a tri-peptide made up of the amino acids L-cysteine, L-glutamine and glycine. Of the three, cysteine is the main source of the free sulfhydryl group of GSH and is a limiting factor in the synthesis of GSH.
Because GSH is known to be essential to immunity, oxidative stress, general well being, and reduced levels of GSH are associated with a long list of diseases, whey has a place in anyone's nutrition program. Reduced GSH is also associated with over training syndrome (OTS) in athletes, so whey may very well have an application in preventing, or at least mitigating, OTS.
GSH is the major intracellular water-soluble antioxidant in the body, which is involved in the recycling of other antioxidants. Twenty healthy young adults (10 men, 10 women) were supplemented with either whey or casein for 3 months. The researchers looked at:
- Muscular performance
- Lymphocyte GSH levels
As one would expect, they found no baseline differences in peak power or work capacity between the whey and casein groups. However, after treatment, a follow up on 18 subjects - 9 who received the whey and 9 who received the casein (considered a placebo in this study) - were analyzed.
Both peak power and work capacity increased significantly in the whey group, with no changes found in the casein group. Lymphocyte GSH also increased by over 35% in the group receiving the whey with no change in the group getting casein.
The researchers concluded, "This is the first study to demonstrate that prolonged supplementation with a product designed to augment antioxidant defenses resulted in improved volitional performance."
As mentioned, due to whey's high biological value and its other properties, such as a high branch chain amino acids content, etc., it has always been theorized whey should be a particularly effective for gaining or preserving muscle mass.
This is one reason whey is the best selling protein on the market with bodybuilders. However, there was very little hard data that directly supported that theory and what did exist was often contradictory.
One recent study in animals however supports the role of whey as being potentially superior in this respect to other proteins. One recent study, looking directly at the effects of different pre-workout drinks and their effects on the muscle mass and body fat, came to some very interesting conclusions.
One thing we have known a long time is the composition of the pre-exercise meal will affect substrate utilization during exercise and thus might affect long-term changes in body weight and composition. That is, depending on what you eat before workout can dictate what you use for energy which alters what you burn for energy.
The researchers took groups of rats and made the poor buggers exercise two hours daily for over five weeks, either in the fasted state or one hour after they ingested a meal enriched wither simple sugar, whole milk protein or whey protein.
The results were quite telling. Compares with fasting (no food), the glucose meal increased glucose oxidation and decreased lipid oxidation during and after exercise. Translated, they burned sugar over fat for their energy source. In contrast, the whole milk protein and whey meals preserved lipid oxidation and increased protein oxidation.
Translated, fat burning was maintained and they used protein as a fuel source. Not surprisingly, the whey meal increased protein oxidation more then the whole milk protein meal, most likely due to the fact that whey is considered a "fast" protein that is absorbed rapidly.
As one would expect by the end of the five weeks body weight was greater in the glucose, whole milks protein and whey fed rats than in the fasted ones. No shock there.
here is where it's gets interesting! In group getting the glucose or the whole milk protein, the increase in weight was from body fat, but in the whey fed group, the increase in weight was from an increase in muscle mass and decrease in body fat.
Only the rats getting the whey before their workout increased muscle mass and decreased their body fat. The researchers theorized this was dues to whey's ability to rapidly deliver amino acids during exercise, but there are probably other factors involved.
For general health and well being, whey gets a big thumb's up. For potential effects on muscle mass and performance, it gets a (very) tentative thumb's up at this time.