What do humans need energy for?

Answer 1

Its just like Car and gas, if you don't put gas then your car won't start. Human body works just like that.

Humans need energy first for basal metabolism and then for physical activities. The proteins, carbohydrates and lipids present in the food we take are or utilized by the body as a source of energy. The amount of energy measured in calories, which is needed to maintain the body while at rest is called the basal metabolic rate (BMR). The BMR is usually lower for women than for men and in general, it is affected by size, shape, weight, age and activity of endocrine glands. In addition, any type of exercise requires still more energy.

We spend energy when we do any type of work such as walking, running (jogging), swimming, dressing and undressing. Even when sitting at resting we spend some energy.