1. Temporary inflammation
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 micro-trauma 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 micro-trauma, 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 in that area that it 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, keep 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.
2. Muscle gain
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 two 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, making the legs increase in diameter. 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 pair of gams.
3. Your diet needs to work
If you’re not following a proper diet you could actually put on fat while starting a new exercise regimen. Yes, exercise burns calories, but it also increases the release of ghrelin, a hormone that promotes hunger. So if you’re not paying attention and not watching your portions sizes, you’ll probably eat more.
Even if you are consuming a low quantity of calories, poor food choices can cause all kinds of issues, usually centered on hormonal imbalances that cause your body to hold onto fat.
4. Too much 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, the stress caused by exercise toughens you up, fortifying your body against further stress.
However, if you pile exercise on top of a bunch of other lifestyle 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 alcoholic drinks a night on a regular basis, smoke, sleep less than seven hours a night, have a chronic injury, eat a junk-filled Standard American Diet and are overweight, exercise will tax your body just like all the bad habits on this list and actually cause weight gain in a couple different ways. First, the inflammation process does not progress to the later phases of healing, and you can end up with chronic inflammation throughout the body. Second, you’ll increase the release of the stress hormone cortisol that, in turn, can promote fat accumulation—particularly fat around the stomach.