To control body fat and weight, many people find it difficult in practice. But the principle behind it is actually quite simple – when intake is greater than expenditure, the excess energy will be stored in the body as fat, which over time can lead to obesity. If you want to reduce body fat, you need to reduce energy intake and increase energy expenditure.
Energy expenditure refers to the energy required by the body’s functions, which can be broadly divided into three categories: basal metabolic rate, physical activity, and thermic effect of food. For the average person who engages in light exercise, the basal metabolic rate usually accounts for about 70% of energy expenditure, physical activity accounts for about 20%, and the thermic effect of food accounts for about 10%. For most people, the biggest difference in energy expenditure is in physical activity.
Physical activity can be divided into two types:
Exercise activity thermogenesis (EAT): structured, planned, and repetitive physical activities performed for the purpose of health, such as running and fitness. The difference in EAT can be quite large depending on individual exercise habits.
Non-exercise activity thermogenesis (NEAT): usually not considered as regular physical exercise, examples include standing, sitting, climbing stairs, cleaning, singing, and other daily activities. NEAT can also vary significantly between individuals, generally ranging between 150-500 calories per day.
Basal metabolic rate is the total number of calories burned when the body is at complete rest, and is also the basic energy required for maintaining breathing, blood circulation, organ function, and basic neural function. For most people, it accounts for about 70% of total energy expenditure – muscles, liver, brain, heart, and digestive system each account for 10-20% (totaling 75%), while the kidneys, fat tissue, and other tissues account for the remaining 25%.
A higher basal metabolic rate means that even if more calories are consumed or if exercise is not done, a healthier body weight can still be maintained. There are many factors that affect basal metabolic rate, including genetics, gender, height, age, climate, and muscle and fat mass. Although most of these factors are difficult to change, you can still increase muscle mass through exercise, which belongs to EAT. Not only can it increase energy expenditure, but it can also increase basal metabolic rate, killing two birds with one stone.
Thermic effect of food, also known as the specific dynamic action of food, refers to the energy required by the body to digest and metabolize food. The amount of energy required depends on the composition of the food, such as digesting protein requires more energy.
Of the three categories, physical activity is actually the easiest to increase energy expenditure. If you can consciously increase EAT and NEAT energy expenditure, and control energy intake with a healthy diet, restoring a healthy body fat and weight is within reach.