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Rate of food consumption in the magic window(10 posts)

Rate of food consumption in the magic windowMcAndrus
Dec 4, 2001 4:56 AM
A question on the rate at which the body turns food into stored energy, either as gylcogen or fat ...

After intense exercise, you're supposed to eat during the magic window to replenish consumed glycogen from the liver and muscles. I read somewhere recently that the body can convert something like 300-400 calories an hour into glycogen and anything more is converted into fat.

If so, this may be the reason people talk about eating several small meals a day instead of three large ones.

I can't site my source, I just remember reading the 300-400 number. Can anyone confirm or deny this?
re: Rate of food consumption in the magic windowmorey
Dec 4, 2001 5:02 AM
The number is irrelative, but good. The reason for many small meals:
1. The stomach is not distended
2. Breakdown of foods is better
3. Absorption/assimilation is better
and yes, if you do get any excess it is converted to fat. It does not matter if this is protein, carb or fat.
However fat has 9cal/gm, prot & carbs 4 cal/gm approx.
re: Rate of food consumption in the magic windowDuane Gran
Dec 4, 2001 7:05 AM
The "magic window" is refered a time right after excercise where the body can re-absorb nutrients more effectively. In studies performed by Ed Burke, there is up to a 40% difference in muscle glycogen storage if you eat something within 30 minutes of vigorous excercise versus 4 hours later. He recommends a post ride diet of 4 parts carbohydrate and 1 part protien.

He wrote a very informative book called "Optimal Muscle Recovery" which addresses many of these issues. It is a good read. He is a big proponent of the Endurox R4 product, which he pushes a bit in the book. I have used it with good success, but my personal preference is to eat a light pasta meal after exercising.

Regarding how much your body can absorb, I have heard the 400 calorie figure. When you consider that cycling can burn 600+ calories an hour it highlights the need to eat while riding on long events.
re: Rate of food consumption in the magic windowmorey
Dec 4, 2001 7:11 AM
Within 1 hour after exercise, the body has maximum absorption and utilization. Protein for repair is used heavily at this time, therefore consumption should be made. We do not need much protein to fulfill this requirement.
re: Rate of food consumption in the magic windowJon
Dec 4, 2001 9:32 AM
The 300to 400 Kcal per hour, I believe, refers to rate of gastric emptying, not rate of glycogen synthesis.
However, there does seem to be a higher level of insulin sensitivity and greater receptivity to gycogen synthesis
in the "window". Morey's right about the protein requirement being fairly small. Several replications were done
on John Ivy's original research which suggested a 4:1 CHO/Pro ratio. The results contradicted his findings and
revealed an arithmetical flaw in the study. Endurox R4 is Ed Burke's proprietary product, which is why he
pushes it! Not that its a bad product. It isn't. But it's expensive. White bread and egg whites in the right proportions
will do the same job for a fraction of the cost. Or Gatorade, or bagels, etc., etc.!
re: Rate of food consumption in the magic windowmorey
Dec 4, 2001 9:42 AM
A good figure for protein is 1gm/kg. For bodybuilders during heavy training maybe 1gm/lb. Protein is very easy to get in the American diet. It definitely is not a good energy source. I would rather eat or drink good food than rely on expensive supplements. I am glad you have figured out that this is a great way to make money!
beware of Salmonella in raw egg whites -NMTig
Dec 4, 2001 10:55 AM
72 hours lag timeBigLeadOutGuy
Dec 4, 2001 4:46 PM
All the info listed here is good. Except no one answered your question about your body storing excess calories as fat. There is usually a lag time of 72 hours for excess calories to be stored as fat. your body doesnt store fat per hour...its a long process for excess calories to be shuttled into the fat cells.
Shakey dataKerry Irons
Dec 5, 2001 10:42 AM
Note that the study behind this "eating window" theory has been shown to be fallacious. It is true that your muscle glycogen is higher after 4 hours if you eat during the "magic window", but after 24 hours, there is no difference in muscle glycogen regardless of your eating pattern. The eating window theory was developed based on the 4 hour data. The 24 hour data have largely made the eating window concept relatively worthless. You need to eat, but when you eat is not nearly so critical as the "window" theory would suggest.
Unless you're doing two-a-days. (nm) Good point!Jon
Dec 6, 2001 6:50 AM