Physical Activity: any movement that uses the skeletal muscles in the body and requires energy to do
Exercise: a type of physical activity that is done for the betterment of your health; actions need to be planned, structured, repetitive and purposely focused.
Fitness: a state of well-being, usually related to physical ability and exercise.
Movement: the act or process of moving part(s) of the body.
Calories: a unit of energy. Calories derive from the food we eat and is then expended to create movement.
Energy: the product needed in order for work to be done.