Weight gain after exercise: Changes in body composition and how to view them correctly

Special concern 14: Weight gain after exercise

To lose weight, the classic path of "controlling your diet and exercising" is unavoidable. Compared to extreme weight loss methods of previous years, such as fasting, the 3-day apple diet, or the 7-day vegetable soup diet, exercise has become the new trend. Many women who exercise to lose weight struggle with one question: "I haven't eaten much, so why have I gained weight after starting to exercise, even with the same diet?"

This is a complex issue, so we need to start with body composition and weight loss goals.

Everyone knows that you can weigh yourself using a scale, but what exactly is body weight made up of? Many people probably haven't thought about that. Our body weight includes the weight of our bones, the weight of our muscles (including visceral muscles and limb muscles), as well as the weight of our blood, lymph, interstitial fluid, and fat. The weight of each of these components and their proportions are called "body composition."

Who wants to have low bone mass? Strong bones are a huge health advantage, and low bone mass often means a higher risk of osteoporosis.

Who wants to have too little muscle? Reduced visceral muscle means decreased metabolic function; reduced limb muscle means weakened physical strength and physiological aging. Overall, muscle loss is directly related to a decrease in metabolic rate, which means reduced energy consumption and can lead to a "prone to weight gain and difficult to lose weight" physique.

Who would want to be dehydrated? Body fluids are extremely important for human health, and body water content is closely related to a person's youth. Infants have the highest body water content, while the elderly have the lowest.

Understanding these basic principles clarifies that when losing weight, we shouldn't be reducing bones, muscles, or body water, but rather fat. Bones, muscles, and water don't harm our health; only excess fat poses a risk of disease. True weight loss involves lowering body fat percentage to a healthy range.

If you only pursue weight loss without focusing on reducing body fat percentage, or even reduce useful parts of your body such as bones and muscles just to make the weight number look "good", you will not only lower your body's metabolic rate, but also damage your health and accelerate aging. This runs counter to the fundamental goal of weight loss.

As detailed earlier, during weight loss, the rate of weight loss differs drastically between reducing fat and reducing muscle (protein). Weight loss methods that reduce protein lead to rapid weight changes, while steadily reducing fat results in a very slow rate of weight loss-so slow that it can be unbearable for impatient dieters.

Losing 1 kg of pure fat requires expending 9000 kcal of energy. Even if a woman eats nothing all day and maintains a normal lifestyle, expending 1800 kcal, she will only lose a little over 200 grams of pure fat, a weight change that is still within the margin of error of a home scale. In terms of energy efficiency, the energy required to lose 1 kg of fat is equivalent to losing 2.25 kg of protein, plus even more water bound to protein. The body expends 9000 kcal of energy to lose only 1 kg of pure fat; while theoretically, the weight loss from reducing pure protein by expending the same amount of energy would be approximately 7 kg.

Returning to the main topic of this section, why does exercise sometimes lead to weight gain?

For those who were originally in poor physical condition, exercise not only burns fat but also strengthens internal organ function and increases the proportion of muscle in body composition. Muscle is denser than water, while fat is less dense than water. If a person trying to lose weight reduces a certain volume of fat and increases an equal volume of muscle protein, then their weight will inevitably increase.

This is most noticeable in the early stages of exercise-based weight loss. Weight may not decrease, or even increase, but the body doesn't become bulky, and clothes may appear too big. This is because body fat percentage decreases, and body circumference gradually decreases. As the metabolic rate gradually increases, the body's ability to break down fat strengthens. If you are overweight or obese, you will see slow but continuous weight loss during this stage.

A woman told me that after exercising for two months, she gained 2 kilograms, but her figure had noticeably improved. Jeans she couldn't fit into before now fit beautifully, her waistline had shrunk, her stomach was flatter, and her buttocks were more lifted. This is a delightful result, because it means she lost almost entirely fat. Only weight loss that lowers body fat percentage is true weight loss, and only weight loss that improves body shape.

However, many women who are trying to lose weight don't feel this way. One woman asked, "Why haven't I lost any weight despite exercising hard for two months? I'm about to give up!"

I replied, "If you dieted diligently for two months and lost a lot of weight, but your figure didn't improve, would you be happy? People only see your body shape; who cares about the weight?"

Unfortunately, because they forget the fundamental goal of weight loss and are overly obsessed with weight data, most people become frustrated in the early stages of exercise because they cannot see weight loss, and their weight loss efforts are abandoned halfway.

Some people might ask, "Exercise can definitely change my body shape, but the weight will come back as soon as I stop!" This is indeed true, but if I don't exercise and switch to other weight loss methods, will the results be better?

(1) Instead of exercising, try dieting to lose weight. Can you starve yourself for the rest of your life? As soon as you stop dieting and start eating three full meals a day, your weight will rebound even faster.

(2) Instead of exercising, try diet pills. Can you take diet pills for the rest of your life? As the saying goes, every medicine has some toxicity. All diet pills have obvious side effects. To date, there is no magic bullet that can make people lose weight without paying any price.

Therefore, methods like starvation and medication are unsustainable and severely damage health. In contrast, exercising three times a week is extremely beneficial for health, vitality, and beauty, so why not stick to it?

Even if it's not for weight loss, but simply to maintain health and prevent chronic diseases, you should ensure at least 150 minutes of exercise per week.

As we age, our metabolic rate gradually decreases, making us more prone to weight gain. Maintaining a healthy physique is a lifelong endeavor; it's crucial to avoid being impatient or fantasizing about achieving it all in one fell swoop.

Eating happily, getting enough nutrition, exercising happily, forgetting the number on the scale, and focusing on building and maintaining a beautiful figure are the keys to high-quality weight loss.