Fitness broadly describes the body’s capacity to cope with demands placed upon it. The more efficiently the body copes as these demands become greater and greater, the fitter the person is said to be. While this might mean that fitness refers to coping with stressful situations such as high altitude or continuous cardiovascular exertion, it also refers to the ability to cope with day to day conditions. For example, someone who is unfit may be able to run a mile, someone who is very unfit however might be in danger of a heart attack or stroke just from moving around their home.