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2.2: What are Physical Activity and Exercise?

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    11127
  • Physical activity is defined as any movement carried out by skeletal muscle that requires energy and is focused on building health. Health benefits include improved blood pressure, blood-lipid profile, and heart health. Acceptable physical activity includes yard work, house cleaning, walking the dog, or taking the stairs instead of the elevator. Physical activity does not have to be done all it once. It can be accumulated through various activities throughout the day. Although typing on a phone or laptop or playing video games does involve skeletal muscle and requires a minimal amount of energy, the amount required is not sufficient to improve health.

    Despite the common knowledge that physical activity is tremendously beneficial to one’s health, rates of activity among Americans continue to be below what is needed. According to the Center for Disease Control (CDC), only 1 in 5 (21%) of American adults meet the recommended physical activity guidelines from the Surgeon General. Less than 3 in 10 high school students get 60 minutes or more of physical activity per day. Non-Hispanic whites (26%) are more active than their Hispanic (16%) and Black counterparts (18%) as is the case for males (54%) and females (46%). Those with more education and those whose household income is higher than poverty level are more likely to be physically active.1

    The word exercise, although often used interchangeably with the phrase physical activity, denotes a sub-category of physical activity. Exercise is a planned, structured, and repetitive movement pattern intended to improve fitness. As a positive side-effect, it significantly improves health as well. Fitness improvements include the heart’s ability to pump blood, increased muscle size, and improved flexibility.

    Components of Health-Related Fitness

    In order to carry out daily activities without being physically overwhelmed, a minimal level of fitness is required. To perform daily activities without fatigue, it is necessary to maintain health in five areas: cardiorespiratory endurance, muscular strength and endurance, flexibility, and body composition. These five areas are called the components of health- related fitness. Development of these areas will improve your quality of life, reduce your risk of chronic disease, and optimize your health and well-being. Each of these 5 areas will be explored in depth at a later time. Below is a brief description of each.

    • Cardiorespiratory enduranceCardiorespiratory endurance is the ability to carry out prolonged, large muscle, dynamic movements at a moderate to high level of intensity. This relates to your heart’s ability to pump blood and your lungs’ ability to take in oxygen.

    • Muscular strength
      Muscular strength is the ability of the muscles to exert force over a single or maximal effort.

    • Muscular endurance
      Muscular endurance is the ability to exert a force over a period of time or repetitions.

    • Flexibility
      Flexibility is the ability to move your joints through a full range of motion.

    • Body Composition
      Body composition is the relative amount of fat mass to fat-free mass.

    As previously stated, these areas are significant in that they influence your quality of life and overall health and wellness.

    Skill-Related Components of Fitness

    In addition to the 5 health-related components, there are 6 skill-related components that assist in developing optimal fitness: speed, agility, coordination, balance, power, and reaction time. Although important, these areas do not directly affect a person’s health. A person’s ability to perform ladder drills (also known as agility drills) is not related to his/her heart health. However, coordination of muscle movements may be helpful in developing muscular strength through resistance training. As such, they may indirectly affect the 5 areas associated with health-related fitness. Skill- related components are more often associated with sports performance and skill development.