More often than not, exercise is synonymous with weight loss. In fact, I create customized workouts for my clients each and every week because they’re that important. But the promise of weight loss as a result of vigorous exercise has been significantly overstated. In fact, some of the greatest frustrations I hear from my clients when we first begin working together is that they believe their workouts make them gain weight. 

Could this be true? Could exercise actually hold you back from shedding unhealthy weight? 

Well…maybe. But don’t blame your workouts. 

Here are 3 big reasons you might gain weight with exercise

…and what you can do about it if it happens. 

1. Your Muscles Are Speaking Up!

It’s Sunday morning. You wake up, lace up your shoes and go for a five-mile run. A few minutes into your run, you feel sweat rolling down your face. After a mile into your run, you start to pick up the pace a little bit. Coming into the home stretch, you decide you still feel good, so you throw in a little strength work. A few sets of squats, shoulder presses and even some ab work for a strong core complete the workout. 

After you shower, you get on with your day feeling a huge sense of accomplishment. Your muscles feel a little fatigued, but that’s to be expected. You drink a little extra water throughout the day to make sure that you stay hydrated and headache-free. 

The next morning, you get up, jump on the scale and [gasp]’ve gained a pound! How can this be? 

Thinking about the day before, you had a great workout, drank plenty of water and didn’t eat anything out of the ordinary or particularly bad…so why the extra pound? 

Why Weight Gain Happened

Rest assured, the most likely explanation you gained a pound (or even two) the day after a solid workout could be related to micro-tears in your muscles. When you workout, especially vigorously, you place stress on your muscles. This stress results in microscopic tears in the muscles you used to propel your body to run fast, do squats, perform shoulder presses and do ab work. 

Micro-tears are absolutely normal and essential to developing strength. The most obvious side effect of micro-tears is something called Delayed Onset Muscle Soreness (DOMS). Physiologically, you’re dealing with acute inflammation related to your workout. This type of pain is exclusively felt in the muscles and can make it hard to walk up stairs, sit down in a chair or even roll over in bed. The result is a little water retention that will go away as soon as the inflammation subsides, usually within a day or two.

Keep drinking water, stretch, avoid overly salty foods, and keep working out! You have nothing to worry about. If you want to get over DOMS faster, get blood circulating through your muscles as soon as possible. The best way to do this is through light cardiovascular activities, such as walking, jogging or jumping on an elliptical. 

2. You’re Burning Fewer Calories Than You Think

I really don’t like to focus on calories. If you’ve ever worked with me, you know this is true. Calories don’t really tell us anything about the quality of the food we’re eating, and can be a distraction from focusing on a truly healthy diet. 

But if you’re experiencing weight gain, even though you’re working out most days of the week, or training for a distance event (i.e. half marathon, marathon) with hopes of dropping a few pounds, and the scale isn't budging, the cause could be related to the volume of food you’re eating relative to the amount you’re exerting yourself. 

When you workout, you burn calories. But calories, for most of us, don’t fall off as quickly as we might think. 

I’ll use running and walking as an example. The average person burns about 100 calories for every mile they run or walk, regardless of pace. So if it takes you eight minutes to run a mile, you’ll burn 100 calories. If it takes you 17 minutes to walk a mile, you’ll burn 100 calories.

If you run five miles, like in the scenario above, you’ll burn about 500 calories. 

If part of the reason for running is to shed a few pounds, then this is great! It takes 3500 calories to make a pound. So if, over the next two weeks, you ran seven times, you should burn an extra 3500 calories and, in theory, lose a pound, right?

Well…not always.

Why weight doesn’t come off the way we think it should

It’s really important to eat around your workouts, but you don’t need to eat as much as you think. In most cases, eating no more than what you’d normally eat, provided it’s healthy, is probably just fine. 

We’ve been conditioned to think that we need sports drinks and energy bars and protein drinks and huge pancake breakfasts after a weekend workout. This is rarely the case. 

You probably don’t need to eat or drink anything immediately after your workout, unless…

  • You’re actively exercising for a solid 90 minutes OR
  • You workout first thing in the morning without eating breakfast beforehand OR
  • You have a metabolic or medical condition (i.e. diabetes), and you know you need to eat regularly
  • You consciously strenuously overloaded your muscles as in the case of a bodybuilder or powerlifter

If you're not ticking any of these boxes, then don't worry about adding more foods into your diet, especially if your goal is weight loss. The best thing to do is to eat on a regular schedule. Don’t eat too close to your workouts. Aim for high quality foods that aren’t high in sugar or other refined carbohydrates. Keep moving. 



3. You’re Gaining Legit Muscle Mass

This is often the excuse given to anyone who gains weight after committing to a workout routine. And quite honestly, it’s the least likely, but it happens..and it’s a good thing! 

Generally speaking, more muscle than fat means you have a healthy body composition. A healthy body composition doesn’t mean that you look better, but you’re healthier, too. 

A less fatty body means that you’re less likely to develop type-two diabetes, heart disease and other chronic conditions that can be difficult, if not impossible, to reverse. 

There is no glory in being a size two if your size-two body is over fat. Gaining a few pounds in muscle and shedding a pound in fat isn’t a bad thing. So often is the case that strong, lean people weigh much more than you’d ever guess. Placing your focus on strength and movement is always healthier than keeping too close of an eye on the scale.  

It’s all about your satellite cells

We’re all born with the same muscle groups, but some of us have a greater amount of muscle mass and satellite cells within the muscle that make it easier to gain this mass in the first place. 

Satellite cells are receptor sites that get a signal to “wake up” when you tear up your muscle (whether by doing a light or heavy activity). The newly awakened satellite cells then send a signal back to repair and regenerate, making the muscle bigger and stronger. 

Men have more of these satellite cells than women, which is part of the reason why men gain more muscle mass than women. But generally speaking, some people have more satellite cells than others, which is part of the reason why you might gain more muscle mass than your best friend, even if you’re the same size, eat the same food and have a carbon copy lifestyle. 

How do you know you’re gaining more muscle and not fat?

One of the most obvious ways is by personal observation. Does it look like you have more muscle definition than you did before?

But the best way to know that you’re gaining muscle and not fat (especially if the scale nudges up or just doesn’t move at all) is to measure yourself. 

Measuring your body at the same key points will give you much better information about the progress you’re making toward a healthier body than a scale ever will. 

Grab a measuring tape and measure your waistline, your chest and your hips. If you see the number on the measuring tape go down, regardless of what the scale says, you’re gaining lean muscle mass, and this is not something you want to change!