Despite eating well and exercising regularly, weight can remain stable or even increase. The reason behind this is metabolic adaptation - a natural mechanism where the body slows down metabolism and reduces energy expenditure to prevent excessive weight loss. Let's explore the scientific foundations of this process and find effective solutions.

What Makes Up Metabolism?

To understand why weight can "plateau" let's break down the components of metabolism:

  • Basal Metabolic Rate (BMR): The energy required to maintain vital functions at rest (about 60-70% of total expenditure).
  • NEAT (Non-Exercise Activity Thermogenesis): Energy spent on daily activities unrelated to structured exercise (e.g., walking, posture maintenance).
  • Thermic Effect of Food (TEF): The energy required to digest and process food (5-10%).
  • Exercise Activity Thermogenesis (EAT): Energy burned during workouts (the smallest portion compared to NEAT).

As we can see, workouts alone are not the main driver of energy expenditure, meaning weight loss depends on a comprehensive approach, not just calories burned at the gym.

Why Does Metabolic Adaptation Happen?

The body is programmed for survival, and when calorie intake decreases, it activates protective mechanisms:

  • Thrifty Gene Theory: Our ancestors faced food scarcity, and those with energy-efficient metabolisms survived. Although modern life no longer involves prolonged starvation, genetic predisposition to energy conservation remains.
  • Adipostat Hypothesis: Fat tissue regulates energy balance through hormones like leptin, ghrelin, and insulin. When fat stores decrease, the body signals, "Preserve energy" which can slow weight loss.
  • Protein-Stat Hypothesis: The body aims to preserve lean muscle mass, so after prolonged caloric restriction, appetite may increase as a compensatory mechanism.

How to Overcome Metabolic Adaptation?

The best strategy is to prevent excessive adaptation. But if you're already experiencing it, here are practical recommendations:

✔ Assess your habits. People often underestimate calorie intake and overestimate physical activity. Keeping a food diary can help.

✔ Use the "zigzag" method. This involves calorie cycling: one day with a 20% deficit, the next at maintenance, followed by a slight surplus. This prevents metabolic slowdown.

✔ Gradually increase calorie intake. If you've been on a low-calorie diet for a long time, raise your intake slowly (+50-100 kcal per week).

✔ Ensure adequate protein intake. The optimal range is 1.2-1.5 g of protein per kg of body weight.

✔ Don't forget fiber. The minimum daily intake should be ~25 g per day (found in vegetables, berries, nuts, seeds, and whole grains).

✔ Control carbohydrate intake. 45-50% of total calories should come from quality carbohydrates: whole grains, legumes, whole wheat bread, and cooled potatoes.

Metabolic adaptation is not a sign that your body is "broken" - it's a natural survival mechanism. Instead of fighting against it, adjust your diet and physical activity with a scientific approach. The process may take time, but consistency and balance always outperform quick fixes.