How Does the Cyclical Ketogenic Diet (aka "Anabolic Diet") Compare With a Calorie-Reduced Mixed Diet?
Is the Anabolic Diet really anabolic?
In the mid-1990s, before the Atkins craze blew up, some bodybuilders were already experimenting with the Cyclical Ketogenic Diet (CKD). This eating plan was introduced to the strength training world by accomplished powerlifter and physician Mauro Di Pasquale, via his book The Anabolic Diet, and the late Dan Duchaine, who wrote about it in his tome BODYOPUS.
A CKD involves 5-6 days of very low-carbohydrate eating (the ketogenic phase) followed by 1-2 days of a very high-carbohydrate intake, repeating the cycle on a weekly basis.
The premise behind the CKD was that the body would accelerate fat burning during the low-carb days, then replenish muscle glycogen stores during the brief high-carb phase.
By way of adjusting caloric intake, it could be used for cutting or for bulking.
So while the original CKD strategy didn't promote the "calories don't count" nonsense, it still embraced the now-disproved belief that carbohydrate restriction per se increased fat loss, while carbohydrate intake promoted fat gain. The two-day high-carb period, we were told, allowed for muscle glycogen replenishment but was not long enough for the alleged fat-depositing effects of carbs to kick in.
We were also told the diet would increase growth hormone levels (hence the "Anabolic" tag). The erroneous belief that low-carbohydrate diets increase growth hormone output was based on the observation that experimental episodes of hypoglycemia (low blood sugar) can be accompanied by increased GH output. The simplistic assumption was that low-carb diets lower blood sugar, so therefore they must raise GH levels.
The assumption was not just simplistic, but wrong. No-one has shown an isocaloric ketogenic diet to cause greater GH output. To trigger GH release, researchers must first give subjects a large dose of glucose that causes initial hyperglycemia (high blood sugar), followed a few hours later by hypoglycemia. It should be noted that hypoglycemia is not a good state to be in. If your diet consistently leaves you hypoglycemic, then your diet sucks.
The initial hyperglycemia in these experiments is accompanied by suppressed GH levels, but three to five hours after the initial bolus of glucose, the subsequent hypoglycemia of these subjects is accompanied by a rise in GH.
Obviously, gulping down large amounts of glucose every 5 hours in the hopes of boosting GH has nothing to do with a low-carbohydrate diet.
Basically, Cyclic Ketogenic diets were built upon a false premise. For the record, I'm not belittling Dr Di Pasquale or Duchaine; the former by all accounts is a sincere and highly knowledgeable individual, the latter was often described as a "mad scientist" who reveled in experimenting with diet, supplements and, infamously, drugs.
Despite its flawed theoretical foundations, the CKD has its devoted followers. Those who understand that strict ketogenic dieting is flawed, but still can't shake off their anti-carb conditioning, believe (hope) there is something special about eating keto during the week, then carb-loading on the weekends.
But is there?
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