What energy transformations occur when humans use energy from food to exercise?

When humans consume food, the chemical energy stored in nutrients is transformed into usable energy through metabolic processes, primarily cellular respiration. This process converts carbohydrates, fats, and proteins into adenosine triphosphate (ATP), which acts as the energy currency for cells. During exercise, this ATP is then used to fuel muscle contractions and various physiological activities, transforming the chemical energy from food into mechanical energy for movement. Additionally, some energy is lost as heat during these transformations.