Why You Gain Weight When First Exercising


Has this ever happened to you:

…You finally started exercising, making time for yourself and eating better – cue your resutls!

You step on the scale, prepared to witness your incredible transformation when OMG……….

Your weight went up???

How is this even possible? 

…You have been exercising more than ever before!

…You are feeling the healthiest you’ve felt in years!

…You’ve made huge improvements with your eating habits!

Is this a cruel joke?!

This frustration is very common and though hard to believe, seeing that bump in scale weight is equally as common when starting a new exercise program, regardless if your new to exercising or not.

Understandably, seeing your weight go up leads you to question if what you’re doing is working.

First, do not panic!

Before getting discouraged and deciding to call it quits, today’s coaches blog is teaching you: 5 reasons the scale goes up when you start a new exercise program so that you can understand:

  • 5 reasons exercising causes weight gain + what this means
  • 3 tips when starting a new exercise program



To put your mind at ease and reinforce you should continue exercising and eating better, it’s important to understand why this is happening. And, have no fear – you are not alone!

#1. Water Rentention:

When you start a new exercise program, regardless if you’re brand new to exercise or the workouts you were doing before, your body goes through many changes.  And don’t be alaarmed as these changes are normal, super common and to be expected during those first few months.

One of those changes = water retention. Note this is a highly common cause for temporary weight gain that will make your scale weight fluctuate anywhere from 2- 4 pounds in a single day.

Why are you retaining water? When you exercise, you are causing some “damage” to your muscles; think small tears in your muscle fibers as your body start building muscle.  This inflammation causes your body to retain water to heal and recover.

This is why we are huge advocates for staying well hydrated! A good rule of thumb is to drink half your body weight in ounces of water daily.

  • Example: if you weigh 150 pounds, your goal is drinking at least 75 ounces of water /day to help your body recover from exercising and aid in healing your muscles.

Next time you step on the scale, keep in mind that up to 60% of the human body is water! Your brain and heart are 73% water, lungs 83% water, skin 64% water and muscles and kidneys 79% water.

That’s alot of water in the body – who would’ve thunk?!

#2. Glyocgen Conversaion:

Next up, glycogen! Your body needs energy to exercise and that energy is created when glycogen (sugar) is converted into glucose. Glucose is then stored in our muscles, serving as your extra energy source to fuel your muscles as you exercise and put new stress on your muscles.

It is important to note Glycogen has to bind with water to give your muscles the energy needed to exercise and do things like lift weights or use other forms of resistance as you exercise. Again, this leads to water retention (see #1 above).

The further along you get in your new exercise routine, the more your body and muscles will adapt and the less glycogen you will need for that extra fuel and energy. Those extra pounds you are seeing because of this extra energy? Those eventually taper and your inflated scale weight will return to your “normal” baseline.

#3. Eating More:

If you’re exercising consistently and still gaining weight, that increase has everything to do with what you’re eating and how much:

If you are new to exercising or starting a new type of exercise program, you will likely feel / notice an increased in daily hunger levels and appetitie due to the incerase in activity. This is super common and completely normal.

When you first startexercising, your body’s adjusting to an increased level of activity (this is a good thing) causing you to feel hungrier during this transition phase as your body adjusts.

Without even realizing it, this could lead you to being in a calorie surplus: eating more calories than you are burning.

Now, you may be thinking, “But if I am exercising more, don’t I need to be eating more?”

When it comes to losing or gaining weight, here’s the science:

  • To lose weight, you must be in a CALORIE DEFICIT: BURNING MORE calories than you are eating.
  • To gain weight, you must be in a CARLOIES SURPLIS: EATING MORE calories than you are burning.

Why does this matter?

Most of us underestimate how much we eat by 30%-40%.  Especially when new to exercise, you likely are eating more than you realize, and this can absolutely be why your weight is going up a few pounds.

It’s also common to think of exercise as an outlet to “eat more” or “burn off” weekend splurges, favorite foods and drinks:

“I exercised today, I can have pizza.” “I was bad this weekend – I need to burn off everything I ate and drank”.

Here’s the truth: You cannot out-train what you eat meaning, you cannot burn enough or level out calories eaten with exercise.  This is a common misconcpetion and at the end of the day, a losing battle.  If you’re constantly eating in a calorie surplus, you will 100% gain weight, regardless of how often/much you exercise.

Another tricky thiing is relying on your smart devices to show ‘calories burned’ when exercising. These devices unfortuatenly overestime calories burnded by a lot.

What you can and should do is think of food as FUEL for your body to help it look, feel and operate at its best by making sure you eat lots of real foods!  This means minimally processed foods and hefty focus on the macronutrients your body needs to get stronger, lose weight, drop body fat,and be leaner: protein, veggies, smart carbs, and heart healthy fats.

#4. Gaining Lean Muscle:

So you step on that scale and the number is going up but remember, the scale can be deceiving!

Does that increase mean you are gaining weight, fat or lean muscle?

When you hear us refer to body composition, this is a fancy way to reference your body’s fat to muscle ratio (how much of your body is made up of fat and how much is made up of muscle).

And, when it comes to gaining fat or muscle, there are some important differences to understand:

Gaining Muscle: To gain muscle, your body needs stregnth-training workotus – exaclty what you do at Results Fitness in Small Group Personal Training!

  • Strength training doesn’t make you a bodybuilder nor does it mean you have to be lifting super duper heavy weights!  Strength training is about having that stimulus/ form of resistance when exercising: kettlebells, dumbbells, barbells, resistance bands, medicine ball …..tons of options regardless of age or experience level.
  • Strength Training makes you stronger, increases bone density and keeps various muscle groups working the right way so daily tasks like getting out of bed, carrying  groceries, picking up kids/grandkids) are easy and pain free!

Gaining Fat: To gain fat, the quality of foods you eat matters just as much, if not more, than the quantity.

  • Sure, you can eat 1,200 calories worth or Oreos and 1,200 calories worth or broccoli and calorie wise, they’re the same. However, your body will process and break each down very differently and nutrient wise, these foods are NOT created equal.
  • Eating more processed foods like Oreos versus real foods results in rapid fat gain.
  • You will feel and experience noticeable differences in the way you look and feel, despite equal calories.

Nutrition is going to be a driving force behind your results so be honest with yourself and take time to understand your eating habits/behaviors and know these play a major role:

  • What types of foods are you consistently eating?
  • What do your portions look like? You can still eat too much of a good thing, especially when it comes to fats like almonds/nuts/seeds, hummus, avocado, etc.
  • Do you nail nutritionMonday-Friday but fall off on the weekends? Consistency counts most and weekends can and will undo your Monday-Friday progress.

Based on your current eating habits, what you are eating can be leading to weight / fat gain.

Comparitively,  pay attention to other factors indicating you are moving in the right direction, despite what the scale says:

  • Are your clothes fitting differently? Pants feel too big?
  • Finding you have more energy during your day?
  • Feeling stronger every workout and able to do a few more reps or use a heavier weight?
  • Feeling less winded and able to recover faster throughout your workout?
  • Are you moving better than before? Less aches and pains?

When it comes to understanding what actually is going on with your body composition, the progress you are making and how your time and efforts exercising are paying off, the scale won’t do you any favors.

Measure progress in different ways gives you better feedback and data – examples:

  • How clothes fit
  • Waist, hip and bust measurements
  • Ability to use heabier weights over time
  • Moving better
  • Less aches and pains
  • Progress photos to see the visual transformation
  • InBody Analysis: fat to muscle ratio (available in the RF studio!)

If you want this to be a permanent change in your lifestyle, the process and those habits/behaviors you repeat daily will be your driving force – not the scale!

#5. Post-workout Inflammation + Soreness 

Your workout may be the very reason you are experiencing weight gain, at least temporarily!

Again, strength/ resistance training causes muscle damage by producing small microtears. When this happens, inflammation occurs as white blood cells rush to the damaged muscle to repair. This repair process allows our muscles to grow and get stronger – this is a very good thing and what you want!

The inflammation and build-up of cells/tissues may very well be the reason for temporary weight gain following your workout. And, if you ever are feeling sore after exercising, this inflammation is to blame.

Keep in mind this is an indicator you are exercising hard enough to see results and, your goal is not feeling “beat up” and sore every time you exercise. You just need to create that stimulus your body needs to change.

So, as you start your new exercise program or transition into trying a new type of workout like strength training, it is a 100% guarantee you will see your weight fluctuate and go up.

But good news – you now know why!

Use the information you learned in this blog to frame your mindset and expectations.

Seeing that number temporarily go up is NOT always a bad thing. As you just read, it can be an important indicator you are on the right path and well on your way to seeing results and living healthy, happy and strong!

Weight loss is NOT a linear process and it is impossible to see immediate results.

If it took time to gain weight and body fat, it is going to take time to lose it.



Here are 3 key practices to keep in mind when you first start exercising:

  1. DON’T let the scale dictate your life! Instead, pay attention to how you feel when you first start working out (i.e. energy levels, confidence, strength, flexibility).
  2. DO eat whole foods and drink plenty of water to stay properly hydrated and fueled, ensuring your body has what it needs to make changes and produce results!
  3. DO allow time for your body to adjust to your new exercise routine and changes in eating. This is a slow and steady process – change DOES NOT overnight!

The key factor is giving your body time to reset, recalibrate and adjust to ALL the new changes you are making inside and outside the gym.

Staying off the scale and focusing instead on how you feel, how your exercise programs/routines are improving, your energy, your mood, how the clothes are fitting….all effective tools for evaluating and tracking your progress.

Remember, losing pounds on the scale doesn’t mean much at all, it just means you’re lighter.  It is not an effective tool for measuring your strength, lean muscle or overall health.


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