Training & Nutrition - took the past week off, ate more, lost weight?

is there an explaination to this? when i say ate more i mean gorged myself on things like cookies and overall junk food in addition to my normal diet which is pretty good (imo)

Same happened to me first week of Dec - went to Walt Disney world for 5 days and a Disney cruise for 3 days. Only rode 4 times in 1.5 weeks and for short durations. Ate like a horse (and not the healthiest, although I tried). Came home weighing 2 lbs lighter than when I left?!? I wonder if it has something to do with an atkins effect - lots of high fat foods does seem to cause weight loss if carbs are restricted. Perhaps a loss of muscle mass offset a gain in fat. Hydration??? Who knows.

probably water weight. Glycogen requires large amounts of water in the cells. If you were not exercising as much, the cells might have decided they did not need as much glyocogen stored up.

Sometimes the food surplus goes towards building muscle. Increase in muscle=higher metabolism. But ModoVincere logic seems more likely.

Yeah, weight changes don't mean a whole lot without body fat percentage checks at the start and end of the period of time in question... since you have no idea whether the lost mass came from muscle, water, or fat.

Yeah I'm more and more convinced that calories in/out is not a complete model. The variable is metabolism, and we're just now getting to understand how the body regulates metabolism up/down depending on training stress and diet.

But look at it from an evolutionary perspective - training load is similar to being in a struggle for survival (fighting long intense battles every day or so, or running for hours to catch a measly squirrel), and limited calories intake means there might not be any more tomorrow - so better hold onto whatever we got. So the body adapts by becoming very efficient, basically running the lowest metabolism possible to accomplish the work. This is why you get so droned out during heavy training period, everything is set on low simmer.

Now, you take some time off (the war's over! we don't have to run to catch food anymore!) and pig out on sugary / fatty stuff (we found fresh fruits and fat critters!) and the body can ramp up the metabolism, make all those long-delayed internal repairs and improvements that have been on hold. And it knows, heck, we don't need all the extra fat / mass because we're so efficient now, and besides we're getting plenty more where that came from, so let it go.

Of course, yo do this too long and the body slacks off and goes back to in-efficient mode. But a few days will do wonders. If you've been training hard before this, I bet you get back on the bike and feel like you're flying.

Anyway, that's my probably distorted view of what I seem to be reading in the literature these days.

Blood volume goes down when not exercising. Weight loss. You lose that pump in your muscles. More weight. Never fear, that weight loss will turn right around a bite you good in a couple of weeks. I get the same thing: when I start working out again after a layoff, I'll gain weight right away, usually a couple of pounds, sometimes three.