CKD vs SKD?

[ManInTheBox]

Here's something I've been wondering about. The CKD enthusiasts claim that the carb up portion of the diet is to replenish glycogen lost and to 'power' the next week's workouts. However, the time to reach ketosis and depletion of glycogen is often quoted in the realm of 2-3 days of low-carbs.

My question is if glycogen goes bye-bye in two days, is the diet really more effective than a standard keto diet at maintaining muscle? If so, is it really noticeable that those two days make a difference?

Or is it the liver glycogen that depletes faster and muscle stores remain for a longer period?

Thinking too much at work... any knowledgeable people on this topic out there to educate me?

[Praetorian]

It takes approx 72 hours to get into ketosis once carbs are dropped below 50g or so....thats 3 days. Carbing up for two days does not spare muscle mass and you do not need those excess carbs to power the next weeks workout...that is antiquated thinking. Ketosis in itself is muscle sparing...see below:

Under ‘normal’ dietary conditions, the body runs on a mix of carbohydrates, protein and fat.
When carbohydrates are removed from the diet, the body’s small stores are quickly depleted.
Consequently, the body is forced to find an alternative fuel to provide energy. One of these fuels is
free fatty acids (FFA), which can be used by most tissues in the body. However, not all organs
can use FFA. For example, the brain and nervous system are unable to use FFA for fuel ;
however, they can use ketone bodies.
Ketone bodies are a by-product of the incomplete breakdown of FFA in the liver. They
serve as a non-carbohydrate, fat-derived fuel for tissues such as the brain. When ketone bodies
are produced at accelerated rates, they accumulate in the bloodstream, causing a metabolic
state called ketosis to develop. Simultaneously, there is a decrease in glucose utilization and
production. Along with this, there is a decrease in the breakdown of protein to be used for energy,
referred to as ‘protein sparing’. Many individuals are drawn to ketogenic diets in an attempt to
lose bodyfat while sparing the loss of lean body mass.


Thus the two days of carb up are actually slowing down fat loss and making the diet less efficient.
A single cheat meal is enough to replenish glycogen stores that are not provided by trace carbs and to increase T4 to T3 conversion.
P