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I just started exercising, why am I gaining weight?

Don't give up just yet!

By

Updated May 16, 2014

Written or reviewed by a board-certified physician. See About.com's Medical Review Board.

Struggling to lose weight
Edwin Remsberg Collection/Digital Vision/Getty Images

Question: I just started exercising, why am I gaining weight?

Answer:

If you've noticed your weight going up after starting an exercise program, try not to panic. It doesn't necessarily mean you're doing anything wrong, nor does it mean you're going in the wrong direction. There can be some obvious and not-so-obvious reasons you're gaining weight.

Are You Really Gaining Fat?

Your first step is to determine if what you're gaining is fat, muscle or water. Muscle is more dense than fat, but it takes up less space. That means, if you gain muscle, your scale weight may go up even as you're slimming down. It's normal for many of us to lose inches, even if we're not losing weight.

Another culprit is water retention.  There's a theory that the body will actually retain water when we exercise, not only as part of the healing process by also as a method of getting glycogen to the body in a more efficient way.  That more efficient fuel system means you may carry around a few extra pounds in water.

Either way, the scale can't tell you any of this, which is why it isn't always the best way to measure progress. Another option is to forget the scale, at least for a little while and get your body fat tested by a trainer at your gym. If that isn't an option, take measurements at different areas of the body on a regular basis. If you're losing inches, you're on the right track. For more, check out 4 Ways to Track Your Weight Loss Progress.

If you've measured yourself in different ways and realized you really are going in the wrong direction, take some time to go through the following possibilities - you may need to make some small changes in your diet to see better results.

1. Eating too many calories. It may seem obvious, but we sometimes eat more after starting an exercise program to compensate for burning those extra calories. Most of us think we're eating a healthy, low-calorie diet but, unless you're keeping a food diary, you don't know how many calories you're really eating. Most people are surprised when they start keeping a journal and adding up the calories--it almost always turns out to be more than they thought. Keep a food diary for at least a week or use an online tracking sight like Calorie Count to get a sense of what and how much you're eating. If it's too much, you can make changes in your diet to reduce your calories. And try to avoid the mindset that says you can eat whatever you want since you're doing all this great exercise. To lose weight, you still need to monitor your calories.

2. Not eating enough calories. It may seem counterintuitive, but eating too little can actually stall your efforts to lose fat. As Cathy Leman, a registered dietician and creator of NutriFit! says, "...if there is a severe restriction in calories, the body may counteract this reduction by slowing down its metabolism." Be sure you're eating enough calories to sustain your body if you've increased your activity.

3. Not giving your body time to respond. Just because you start exercising doesn't always mean your body will respond to that immediately. As Cathy Leman puts it, "...in some instances the body needs to sort of "recalibrate"' itself. Increased activity and new eating habits (taking in more or less calories) require the body to make adjustments." Cathy recommends that you give yourself several weeks or months for your body to respond to what you're doing.

4. Rule out any medical conditions. While not everyone suffers from thyroid problems, they can cause weight gain and make weight loss more challenging. You should also check with your doctor about any medications you're taking that could affect your body's ability to lose weight. If you feel your food intake is reasonable and you've given your body enough time to see results and haven't seen any (or are seeing unexplainable weight gain) see your doctor to rule any other causes.

5. You're gaining muscle faster than you're losing fat. If it seems that you're getting bigger after you've started a weight training routine, it may be because you aren't losing body fat as fast as you're building muscle, a common problem. Genetics can play a role; some people put on muscle more easily than others. If that's the case for you, don't stop training. Instead, you might simply adjust your program to make sure you're getting enough cardio exercise to promote weight loss and focus your strength training workouts on muscular endurance by keeping the reps between 12-16.

Whatever the cause of your weight gain, don't give up on exercise!  It's often a temporary situation that will correct itself if you just keep going and, if it doesn't, don't give up all that great exercise time you've collected.  Consider hiring a trainer or meeting with a dietician to help you tweak your workouts and diet.  Sometimes, all you need are a few changes to make a difference.

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