Why do I weigh more after working out?

Well during the course of a normal day, your weight can fluctuate up to 3 lbs naturally. So if it's just a small shift you're seeing, I wouldn't even give it a second thought. Also, after you work out, your muscles are all fired up and actually cause a small increase in weight. Again this shouldn't be more than a pound or two at most. However, this shouldn't last into the next day as well. It's entirely possible that you're just building muscle as well. All in all, if this is the natural rhythm for you, and you're still seeing a general downwards weight shift - I wouldn't worry about it. Just ensure that you're getting all your nutrients and drinking plenty of water.

Aloha Carrie,
I too have the problem. It is a bit discouraging....but the way I feel after a good run makes up for those numbers on the scale. I just wish the scale would reflect my progress. One thing I have started doing is taking monthly pictures to track my weight loss/body transformation. I lose very little weight, but a lot of inches. Perhaps your body is similar.

OK, Blue, I'm gonna take a shot at this from my own thought process and the horrifying amount of research I've done on human anatomy, I've never actually seen the answer to this one in any of my reading.

So I'm going to walk through this logically, see if you guys can follow (and remember, this is kinda an educated guess here).

-so muscles use glycogen for energy.
-Glycogen is a water/glucose "slurry" that is mostly stored in the liver, but also some in the muscles.
-Water is heavy, whether or not there's glucose in it.
-When we exercise hard, we deplete the glucose in the glycogen
-We don't do anything particular with the water that comes along with that glucose. It's just reused by the many things that the body requires water for.
-Some is removed via sweat, some via urine, but the body now perceives a need for extra energy because you burned extra.
-so you have a little bit of extra water in the body, mixed with the body's need for extra energy and thus more glycogen production (and even more water).
-that could probably add up to 2 to 3 lbs.
-Plus, when we wake up in the morning, we are usually in some form of dehydration (6 to 10 hours of no water intake will always mean you're low on your hydration levels) so if you weigh yourself in the morning before drinking water, then weigh yourself during the day, guess what, you're probably going to have a few lbs difference anyway.

I've seen this pattern as well with my runs. If I weight myself the day after a hard run, I weight sometimes up to 2 lbs more. If I wait and rest a few days, then weigh in first thing in the morning, my weight actually sometimes goes down.

I did my own research a little bit, but there's not too much out there. What I *think* from what I've read is that when you work your muscles pretty hard, they obviously tear slightly, and during the rebuilding process they retain excess water/fluid, almost like swelling.

that was simple and right to the point

I know exactly how you're feeling. Now, close to my goal, it is very difficult to make the scale budge. I was very frustrated and didn't/didn't want to understand why. All this talk about starvation mode was too bad and to easy an explanation. Also I didn't believe in eating more to lose because of my age and slower metabolism. I found this her in an other thread. Warning: it is a very long read but I promise: after having read that you will be happier, you will understand and won't be to scared of the scales any more.
Let me know what you think about the article. I've even printed it out.

http://body-improvements.com/resources/eat/

Interesting...I run and I usually weigh less.I thought it was dehydration

I have no creditials to back this up, just that I read a lot and retain a lot of random trivia. So I could be wrong because I can't remember where I read this and therefore can't give sources but:

When you work out you get little "micro-tears" in your muscle and these can pool with blood or other bodily fluids. As these micro-tears heal they are repaired with muscle tissue thus growing your muscles.

So I think you are on track with the fluid thing. I think I read this in "marathon training for dummies". It's why the author suggested cold baths, showers after runs instead of warm ones, warm ones encourage blood to pool making "micro bruises" and increasing the soreness factor.

I know exactly what you are talking about! This holds true for me too! It doesn't matter if it is a 3 mile brisk walk or a long set of weight lifting. All of the same circumstances with diet and water consumption along with the weight fluctuations have nothing to do with it but more with the accumulation of acids in the muscle and the retention of water in my long muscles and limbs. It definitely lasts 2-3 days for me but as long as I continue to be diligent with food and exercise it will pay off. Just as soon as it comes it drops within 2-3 days with a positive affect. This has always been true for me and I've come to accept it. I've recently lost 72 lbs and it is still true as I try and finish my last 50 lbs. DO NOT let it discourage you it is just how our bodies work. It became a trap for me I'd work my butt off and my food was on and then the scale would say up 2-4 lbs. I would be like what!!!! Then I would over eat and go on the crazy cycle. Good Luck! Stay Focused !

This may be a weird question but I've noticed lately that I weigh more after working out. I'm not even talking about RIGHT after working out, but even within the next day or two. For example, I may work out for four days and I'll notice my weight going (and staying) up. Then I'll have a rest day and weigh myself the day after that, only to see my weight's gone back down again.

Is there a reason for this or am I just totally crazy?

EDIT TO ADD:

I really only weigh myself once a week, and that's the only weigh-in I 'count', but I do weigh myself every morning under the same circumstances, just to better understand/track patterns as they emerge....

When you exercise, especially resistance training, your muscle uses up stored energy in the form of glycogen. Upon rest your muscles begin to recover which means an influx of glycogen (which comes with a lot of water). The glycogen/water is to refuel and additional water sheathing the muscle is for repair to the tissue which becomes inflamed from exercise.

You aren't crazy, its perfectly normal. Another thing to note is a lot of people confuse this swelling due to water retention in the muscles with muscle growth. Your muscles will feel harder, they will look bigger, but if you are dieting you aren't adding muscle so that perception just comes from the swelling due to water retention.

Great topic! I actually found it by doing a google search for the same thing because I too was frustrated by doing everything right and the scale fighting me every step of the way and then having a weight loss drop. This thread helped me see things in a different light in my case.
I generally don't like rest days because it feels too easy to slip back into being sedentary so I generally have some form of workout everyday. Except when (sorry guys) I have my TOM, that usually zaps my energy and I don't do my normal routine. I have up to this point always associated my weight loss drops with my TOM because a couple days after that ends is usually when I get my drop but thanks to this thread I'm beginning to think that's it's ALSO due to that's the only time I take rest days!
Maybe I'll throw in a rest day and see if the scale reflects it just to test this theory but I wont be making a habit of it, lol! As long as at the end of the month I've met my weight loss goal I'll be happy! :-)