Gaining Weight While Going to the Gym: Why?

Like everything we start from scratch, we can't measure performance by the initial results. Consistency and controlled diet and hydration will have a significant effect on the medium and short-term rewards of working out at the gym.
Gaining Weight While Going to the Gym: Why?

Last update: 05 July, 2018

One of the main reasons many people go to the gym is to lose weight. Nevertheless, even while maintaining a healthy diet, the first few weeks may result in gaining weight. Why does this happen? Has it happened to you? We will explain the causes behind this phenomenon.

First, though, we want to encourage you to keep making efforts to maintain a healthy lifestyle and be athletically active. Do not get discouraged if you find yourself gaining weight during the first few weeks. There are perfectly good reasons for this, and positive results will soon follow. Do not miss out on the helpful information in this article.

Why is going to the gym linked to gaining weight?

The body needs to adapt to new routines, and exercise is no exception. This is especially true if you have never exercised, or if it has been a long time since you have done any. Transitioning from a sedentary lifestyle to a more active one is a process. These are the reasons why we gain weight.

Success comes when your dreams are stronger than your excuses.

Man and woman drinking water


When we start exercising, our body’s cells require more liquid. This is one of the reasons we gain weight. This “excess” hydration is what helps our muscles tone up and our joints to function properly.

As you exercise, your body will let you know how much water you should drink, which will probably be much more than you are used to. This is why the scale may indicate weight gain, but this is temporary.


Exercise not only burns fat, but it also feeds muscle mass, which is another reason why you may weigh more. We understand that it can be discouraging to make an effort to lose weight, only to put on pounds.

However, you must remember that this process is nothing more than your body converting fat into muscle, which is a good thing. If you are a man, you will probably have to do more cardio and less weights, in order to avoid the increased muscle mass which can make you look heavier.

Meanwhile, women burn fat much faster with weights. These will not cause excessive muscle mass because women do not have a natural source of testosterone. So forget the myth that weights will make you look heavier. If you want to lose weight, incorporate weights whenever you can.

A controlled diet

Woman eating a kebab

A very common mistake is to eat more than usual when going to the gym, thinking that the exercise will compensate for the change. This is partially true, but it is useful mostly for people looking to maintain their weight.

If you want to lose weight, you should forget this idea. You should not eat more because you exercise. In fact, you should eat less. This way, you will see positive results by adopting healthy practices in both respects.


Working out can cause inflammation due to a process known as hypertrophy. When muscles take on weights they are not used to, they experience micro-tears that can cause aches, pains, and stiffness.

The method that the body uses to recover from these micro-tears include inflammation. This protects and surrounds the muscle against the damage that may be caused. As a result, it is possible that even as you work out, you will notice that you feel heavy and stiff, and that your clothes are tighter. Don’t worry: this will pass in a few days.

Woman experiencing soreness


Cortisol is a natural hormone produced by our body, especially in stressful and dangerous situations. It is possible that the exercise is relaxing you, but the inside of your body feels “scared” by the unknown, and enters into a state of fright, that you may not even be aware of.

Your body then begins to secrete this hormone, which breaks down proteins and prevents the increase of muscle mass and the burning of fat. This often happens among experienced athletes when they overtrain.

As you can see, exercise is not at all harmful. Although you may not notice during the first few weeks, your body is undergoing changes that will benefit your health and appearance in the long run. Gaining weight initially may be discouraging, but do not give up!

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There are lots of ways to lose weight, including maintaining a balanced diet and leading a structured life that includes regular  exercise.


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The contents of this publication are written for informational purposes. At no time do they facilitate or replace the diagnoses, treatments, or recommendations of a professional. Consult your trusted specialist if you have any doubts and seek their approval before beginning any procedure.