4 Reasons Working Out Could Be Causing You to Gain Weight

Woman running on beach

The Short Answer
Right off the bat, it’s important to note that this doesn’t happen to everyone, so this isn’t a preemptive excuse not to exercise! However, if you do happen to gain a few pounds when starting a new program, odds are that it’s not fat, but rather temporary water weight due to inflammation. Give it some time and it will pass.

That said, it might be a few other things, all of them fixable, so let’s run through the list and see if we can find a match.


The Long Answer
The most likely reason your scale crept up is inflammation. When you work out, it causes little tears in your muscle fibers. This is called microtrauma and it’s why you feel sore after a workout. On the upside, your body heals these little tears, making the fibers tougher than they originally were. That’s how you become stronger and fitter. It’s part of a process called adaptation.

To make these repairs, your body uses its standard healing process, including the inflammation phase—something that’s become a dirty word in our modern world. When you incur injury, including microtrauma, your body releases various substances generally known as inflammatory mediators that swarm the area and perform triage, bringing in healing white blood cells and opening up blood vessels to flush out debris and toxins. There’s so much going on that the area swells up, or inflames.

The fluid required for inflammatory response obviously weighs something—and that might show up on the scale. When inflammation is allowed to occur in a healthy way, it’s temporary.

Of course, keeping your diet healthy and allowing for adequate rest and recovery will help speed the body to less inflammatory phases of healing, but the main key is to keep calm and carry on. If you’re new to fitness—or perhaps just new to a particular kind of fitness—there’s going to be a lot of adaptation going on and therefore a noticeable level of inflammation. It should subside in a couple weeks.

Another less-likely reason you’re gaining weight is that you’re building muscle faster than you’re shedding fat. The general consensus in the fitness community is that the most weight someone new to fitness will gain in muscle is about 2 pounds a month, but that’s not a hard-and-fast number.

On more than one occasion, I’ve assisted women who are frustrated because they felt their new exercise regime was making their thighs fat. Indeed, their legs were getting bigger, but only because increased muscle under adipose tissue was pushing out the fat and making it appear to increase. Again, the trick here is patience. Once that fat burns off—which it does if you keep at it—thick legs will give way to a toned, sexy pair of gams.


What if Something Actually is Going Wrong?
There are a couple situations in which you might actually be putting on fat. The first one would be that you’re not following a proper diet. Yes, exercise burns calories, but it also increases release of ghrelin, a hormone that promotes hunger. So if you’re not paying attention, you’ll probably eat more.

Even if you are eating at a deficit, poor food choices can cause all kinds of issues, usually centered on hormonal imbalances that cause your body to hold onto fat. Every one of Beachbody’s programs comes with some sort of nutrition guide that should alleviate this issue. Don’t be afraid to read the white book that came with your DVDs.

Finally, there’s the issue of excess stress. Exercise is a good thing, but it also puts your body under stress. By itself, that’s great. It’s part of that adaptation I mentioned earlier. If done right with the proper nutritional support, rest, and recovery, it toughens you up, fortifying your body against further stress.

However, when you just pile exercise on top of a bunch of other stress—or if you work out beyond your limits—balance will be lost. Exercise will contribute to your total stress load, becoming part of the problem as opposed to part of the solution.

So if you work twelve hours a day, drink more than two standard alcoholic drinks a night on a regular basis, smoke, sleep less than 7–8 hours a night, eat a junk-filled Standard American Diet or an overly restricted low-calorie diet, and attempt one of our graduate programs when you’re 100 pounds overweight with a history of knee issues, exercise will tax your body just like all the bad habits on that list. In terms of weight gain, this can manifest in a few ways. First, that inflammation we discussed earlier won’t have the chance to give way to later phases of healing. When this happens, it can become chronic and systemic. Second, you’ll promote the release of the stress hormone cortisol that, in turn, can promote fat accumulation—particularly around the abdomen.

I’m not telling you not to exercise. Just the opposite, in fact. However, fitness is a holistic issue. If your goal is to lose weight, build muscle, or get healthier, you might want to take a closer look at your sleep, dietary, and other lifestyle habits. Sparta wasn’t built in a day. If you’re looking for 300-esque abs, it’s going to take a little time (or some expensive CGI), so start with a program you can do and that will keep you motivated instead of burning you out.

Don’t give up. Give your unexpected added pounds a couple of weeks to work themselves out. If they don’t, step back and see if there’s any other aspect of your life that needs fine-tuning. And come see us on the Expert Advice section of Beachbody Message Boards. We’ll have a look under the hood, and have you back in action in no time.

Do you have a question for our Ask the Expert column? Post it below! For fast, personalized answers, please visit the Expert Forums.

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  1. NEWTAMY said:

    I struggle with menopause. I have at least 2-3 periods a month. All the classic systoms. Especailly the bloating , the chocolate cravings and constantly sweating! I understand with regular periods this is normal. But with menopause this makes for a constant roller coaster of weight gain. I just need to lose 10 lbs but I’m unable to get off this 3 month platue and get down to where I’m happy with myself again. Any advice with this! I’m not giving up just getting frustrated! 🙁

    • Angela said:

      Ive been reading alot about this lately and learning about hormonal imbalance in pre menopausal and menopausal women. One thing they all had in common was diet and eliminating certain foods that cause hormonal imbalance which leads to cravings, weight gain, and a lot of other symptoms.

    • runmom said:

      If you are having 2-3 periods a month, you really should talk to your doctor if you have not already. There could be something more going on that could cause bigger problems for you than the symptoms you are experiencing now. I had issues with my cycle and ended up having to have uterine polyps removed, as that is what was causing my long, heavy cycles. Please talk to your ob/gyn so you don’t end up with bigger problems later.

  2. Drea said:

    I am a 42yrs old female I work 12hrs shift from being active to 3yrs sitting at the desk I’ve gained 40 lbs in the 3 yrs now I am back being active but the weight is harder getting off.. My eating habits are the same.. any advice for me also I am going thru premenopausal

  3. hannah said:

    I work 3 jobs, one at an office, one is ran out of my car, and one is a server at tho fridays, I am constantly on the go, and I’m burnt out on salad. Sleep has never come easy to me, I fall asleep typically around 2 am and wake up around 8 everyday. By the end of the day I’m so tired I can barely stand up out of my car to get inside my house. What should I do?

    • Mark said:

      Try and eat a healthy diet of healthy fats carbs and protiens. Cut back on your hours and try to average 7 hours of sleep or more per night. Remember, you have to invest in your own health and well being because nobody else will!Good luck Hannah!!

  4. John said:

    There is another explanation for weight gain due to increased exercise. See //www.sparkpeople.com/blog/blog.asp?post=you_asked_why_did_i_gain_weight_after_starting_an_exercise_plan

    It states, “When you start doing more exercise, your body begins storing more fuel in your muscle cells, where it can be used easily and quickly to fuel your workouts. The process of converting glucose (carbohydrates) into fuel that your muscles actually store and use (glycogen) requires three molecules of water for every molecule of glucose. As your muscles are building up glycogen stores, your body has to retain extra water for this purpose. That’s what causes most of the initial weight gain or lack of weight loss. This is a good thing–not something to worry about.”

  5. NEWTAMY said:

    I did the 21 day fix also. It helped my portion control and realizing I needed more veggies. But still didn’t straight my hormone imbalance or my irregular periods. With regular periods. Theres a week of bloating ,cravings,etc. Then a 3 week break,generally. But this menopause is really tripping me up. I get maybe a 2 day break, then a week of being uncomfortable .2-3 day break and then a 2 week periods and so on and so on…………

  6. susan said:

    I have struggle for years with my weight going to my stomach. I work out 3 to 4 time a week and have a personal trainer. I don’t eat much bread,cheese or starch just a little. I have muscle under the fat but don’t know how to get rid of the fat on top.

    • Rosa Santos said:

      Susan I know how frustrating it is what I have learned that there are often times gaps in our diets that we miss somehow I have a FREE 5 day group coming up if you are looking to see where the gaps are I can help find me on Facebook.com/fitmom84 🙂

  7. Amy said:

    Thanks for the info. This is what happened to me. I started doing Focus T 25 workouts and my scale went up 2 pounds. I eat pretty healthy too. Hoping the next month for the scales to go down

    • Dirk Smith said:

      I had the same thing happen Amy, but I continued and as my body adapted, the weight started coming off. plus I have better energy thru-out the day so I’m more active..
      Stick with it, it just gets better and better. You can do it.

  8. Richard Hamm-Brown said:

    Hi, Im a wind turbine technician. Yes I climb around 300ft to perform troubleshooting, repair, and maintenance. Sometimes I climb 3 or 4 times a day. With my job I don’t get a break when I perform maintenance from around 0830 to 1430 I’m up tower to do a rigor of thing only sometimes depending on how the work is going for the day get a small lunch or what ever I can carry with me up tower. How can I better benefit losing weight when I only have time for a sandwich or something small that I can carry up tower. Suggestions on meal replacement bars or where to look for such foods would be helpful.

  9. Marielle Benningen said:

    I am struggling to lose the last 10 lbs. I lost 20-22 lbs on 21 day fix but have been stalled for the last 3 months. I am still following the portion control; but am not getting anywhere. I started the H&C but gained even more weight.I exercise 6 days a week. HELP! am very very frustrated!

  10. Heather Y Vincent said:

    I’m wondering if there is something I can do to replace lunges? I have really bad knees, a lot of it I’m sure is due to being overweight. That being said, lunges cause me so much pain, even the modified version. I’m hoping that as I continue thru this process, build muscle and lose weight, lunges won’t be so hard. In the meantime, what, if anything can I do to replace them?