What is the SI unit of energy?

The SI unit of energy is the joule. This unit is defined as the amount of energy transferred when a force of one newton is applied over a distance of one meter. In practical terms, a joule quantifies the work done or the energy spent in various physical processes. It is a fundamental measurement in physics, making it essential for understanding energy in both scientific research and applications, including sports nutrition and exercise science.

Calorie, while commonly used to measure energy in food and nutrition, is not the SI unit and is instead a derived unit based on the energy required to raise the temperature of water. The watt is the SI unit of power, which is the rate of energy transfer and is defined as one joule per second. Newton is the SI unit of force, not energy. Understanding the role of these units helps clarify their distinctions and their specific applications in various fields, including nutrition and exercise.