Final answer:
The term 'expenditure' refers to the energy spent during physical activities, which include anything from minor movements to intense exercises which aim to improve fitness.
Step-by-step explanation:
The word expenditure in the excerpt is used to denote the energy that is spent or used up during physical activity through movement of the body's skeletal muscles. Physical activity ranges from minimal movements like resting to high-intensity efforts like maximal exertion. The structured nature of exercise is intentional, aiming to develop and maintain physical fitness and is a subset of the broader spectrum of physical activities.
Physical exercise encompasses any bodily activity that works to enhance or maintain physical fitness and overall well-being, and can include activities not specifically aimed at this objective, like chores. It is recommended for adults to engage in at least 30 minutes of moderate exercise daily to maintain good health. Various forms of exercise, such as aerobic, anaerobic, and flexibility exercises, each have unique benefits for the body.