Lost 5 lbs in 1 1/2 weeks not lifting and gained all back in day?

[Rachel0208]

Hi, would appreciate some information on why this happened: I had been very busy and could not lift for almost two weeks. I noticed I was losing weight on the scale I went from 126 to 121 in that short of a time. I also noticed the muscles in my arms going down. I finally lifted yesterday and again today and stepped on the scale to see I had gained all those 5 lbs back in two days. Is it possible that I lost 5 lbs of muscle and just gained it all back? I am already a very low body fat at around 10% so I'm not too concerned about gaining the weight back. I just want to make sure it is in fact muscle and not water or fat. I have just never had this happen to me. I am scared that it may be fat because of how I lift and how much muscle I have, I eat a hefty amount of carbs to keep my muscles satisfied and keep my energy level up. Advice?

[illiniStrive]

In the span of less than two weeks it's not likely (or possible?) that you lost that much muscle that quickly, nor that you gained muscle that quickly. The quick weight change is most likely due to water.

[BestYearEver]

Agree it is likely water weight fluctuations.

However, if it is not water, you probably lost muscle and gained back fat. No way you can put on 5 pounds of muscle overnight, in a week, or a month. Burning a pound of muscle doesn't give your body 3500 calories to use for energy, only about 600 calories (from Lyle mcdonald's website). So in a time of stress, inadequate eating, poor macros, not working out, etc. -- if you hit the wrong combo, it is possible to do a recomposition the bad way and lose lots more muscle than you would on a carefully planned cut. If you have very low body fat, this is more likely to happen.

[StangBanger]

water...

[PlzN0Alesana]

well unless u ate 17500 calories above maintenance that one day, u didn't gain 5 lbs of fat back, its water fluctuations.