Skip to main content
Medicine LibreTexts

15.1: Chapter Introduction

  • Page ID
    2978
  • Physical activity is divided into three types: inactivity, non-exercise activity, and exercise.  Sitting and laying down comprise physical inactivity.  Many people spend a substantial portion of their day inactive or sedentary.  How about you?  Have you ever counted how many hours a day you spend inactive?

    Non-exercise activity (also known as NEAT) includes activities that are not sleeping, eating or sports-like activities like walking, standing, gardening, typing, performing yard work, fidgeting, and cleaning house.  Exercise is the third type of physical activity and includes anything that is a sport-like exercise, for example, swimming, running, and bicycling. Exercise activities can be further divided into aerobic and anaerobic which will be explained in this chapter.

    Physical activity confers many benefits.  It improves our mental outlook and capacity, our self-image, our self-confidence, and provides independence for the elderly. Moving can also increase lean body mass and decrease body fat.  Research studies find people who are obese spend significantly more time during the day physically inactive than people who are not overweight or obese. Engaging in physical activity also increases bone mass, and heart, lung, and muscle function.  Morbidly and mortality is lower in people who are physically active compared to people who are sedentary.  Also, the risk is reduced for cardiovascular disease, hypertension, stroke, type II diabetes, cancer, particularly colon and breast, osteoporosis and gall bladder disease.