Myth #2: Precompetition carbo-loading does "pump"

As for the second myth from the attack on bodybuilding practices (which can be viewed at http://www.pponline.co.uk/encyc/0409.htm), carb loading, when done in the proper context of nutritional preparation, DOES result in a cell volumization that, in fact, would never be achieved in any other setting (marathon runner or otherwise). As the previous thread discusses, a cutting phase requires the competitive bodybuilder to cycle carbs such that transient states of ketosis stimulate continual fat utilization without excessively degrading muscle. Provided a generally high protein, low fat, low carb diet concurrent with high intensity, high volume training sessions and large amounts of cardio, the athlete is faced with a gradually diminishing amount of intramuscular and intrahepatic glycogen stores. As glycogen requires an enormous amount of water to facilitate its storage, the bodybuilder tends to appear flatter in muscularity as the competition draws near. This is necessary, however, as the body will preferentially preserve fat at the expense of glycogen at these exceptionally low ranges for bodyfat. That is, there are two stimulants for continued breakdown of fat stores at this stage: ketotic cycles that upregulate lipolytic enzymes and the sheer fact that glycogen stores are increasingly low.

About 1 week away from competition, many athletes will engage in a few days of pure carbohydrate depletion, limiting themselves to as little as 50 g per day. Continuing to train despite their losses in strength and energy, as well as irritability, they truly deplete the muscle, all the while water loading for reasons I will come to in dispelling the later myths. The day prior and of the competition, the athletes eat massive quantities of quality carbohydrates in order to expand the volume of their muscle cells. In essence, the bodybuilder has done the following:
1. Made himself extremely insulin-sensitive given his prior continued exercise and few carbs
2. Subsequently allowed for maximum uptake of glucose into the muscle without inducing a "spill-over" in which excess glucose is stored as fat
3. Induced a fluid shift from extracellular to intracellular as facilitated by the hydration of carbohydrate storage (and aided by other hormonal manipulations to be discussed soon)
4. Expanded the width of the muscle by increasing sarcoplasmic volume.

Granted, this is an illusion. The bodybuilder is no more "pumped" than he or she was prior to the cutting phase, and the cell is not expanded beyond what it was in the bulking season. However, the cell is significantly larger than it was in its depleted state several days earlier, owing mostly to water and glycogen. The key thing is that composition is now as low as 2-3% bodyfat in males and 8-10% in females. This process is the only way to both have fullness of musculature and visibility of physique beneath scant amounts of subcutaneous fat and fluid (unless, of course, you're a genetic freak!)

A further key distinction from the woefully presented marathon runner is adaptation of function. (And by woefully presented I don't mean that runners are woeful--I mean that the author's physiology was poor in comparing a bodybuilder to a runner!) The bodybuilder has greater intramuscular vascularity in the majority of muscles than does the runner. Furthermore, the strength athlete has significantly more mitochondria, nuclei, and other cellular organelles within the muscle, and both organelle volume and vascularity do not disappear during the cutting phase. Thus the bodybuilder has a greater capacity to "expand" cell volume by replenishing carbohydrates and intracellular hydration.

Hopefully this clears up the confusion regarding carb loading in bodybuilders...once again it's an issue of normal physiology in a very abnormal type of athlete. More to follow......