How is potential energy measured for consumption or expenditure

Most materials are subject to thermal expansion: a tendency to expand when heated, and to contract when cooled. For this reason, bridges are built with metal expansion joints, so that they can expand and contract without causing faults in the overall structure of the bridge. But thermal expansion can sometimes also be advantageous, making possible the workings of thermometers and thermostats.

Health educator or sports physician

The answer would be a (carbohydrates)