IMPORTANCE OF EXERCISE - Human beings were designed for movement but few occupations (plus our typical lifestyle) provide enough to maintain health and fitness.
- Peak fitness occurs at physiological maturity (late teens early twenties). After this, life becomes a slide down the aging curve, especially if sedentary.
- Sedentary individuals may gradually lose 1 to 3 percent per year of their cardiorespiratory endurance, muscle mass, and flexibility.
- There is an epidemic of hypokinetic diseases in the modern world. These are diseases of under active lifestyle such as obesity, coronary heart disease, osteoporosis, and diabetes. They cause approximately 250,000 deaths per year.
- "Use it or lose it" has never been more true.
PHYSICAL ACTIVITY AND HEALTH: A REPORT OF THE SURGEON GENERAL - The report revealed that 60 percent of Americans are not regularly active; worse, 25 percent are not active at all; and nearly 85 percent need more physical activity to improve their health.
- The report's conclusions were:
- People of all ages can benefit from regular physical activity.
- Most days of the week should include moderate levels of activity - activity that uses 150 calories per day or 1000 calories per week.
- Cardiorespiratory endurance activity should be supplemented with strength developing exercises at least twice per week.
- Physical activity's benefits include: reduces risk of dying prematurely; reduces risk of dying from coronary heart disease, of developing high blood pressure, cancer, diabetes; helps educe body fat and control weight; helps reduce high blood pressure in people who already have it; helps build and maintain strong bones, muscles, and joints; reduces anxiety, depression, improves mood; and promotes psychological well-being.
- Moderate activity does not have to be punishing or be at one time to be beneficial.
- Examples of moderate physical activity can be found on level one of the Activity Pyramid.
WHAT IS PHYSICAL FITNESS? - It is the ability of the body to function at optimal efficiency.
- It involves skill-related components (speed, power, agility, balance, reaction time, and coordination) and the more important five health-related fitness components (cardiorespiratory endurance, muscular strength, muscular endurance, flexibility, and body composition).
CARDIORESPIRATORY ENDURANCE (CRE) - This is probably the most important fitness component.
- It is the ability of the heart, blood vessels, and lungs to deliver oxygen and essential nutrients to the working muscles and to remove waste products during vigorous physical activity.
- CRE is often expressed in terms of your maximal oxygen uptake (MAX VO2), the greatest amount of oxygen that can be used by the body during intense exercise.
- Running, walking, cycling, and swimming promote CRE.
MUSCULAR STRENGTH - This is the ability of a muscle to exert one maximal force against resistance.
- Short duration, high intensity efforts such as moving furniture, lifting a heavy suitcase, or lifting a 100 pound weight one time are examples.
MUSCULAR ENDURANCE - This is the ability of the muscle to exert repeated force against resistance or to sustain muscular contraction.
- It is characterized by activities of long duration but low intensity such as doing repetitions of push-ups or sit-ups.
FLEXIBILITY - This is the movement of a joint through a full-range of motion.
- Flexibility is essential to smooth, efficient movement and may help prevent muscle strains.
BODY COMPOSITION - This is the amount of body fat in proportion to fat-free weight.
- The ratio between body fat and fat-free weight is a better gauge of fatness than body weight alone.
PHYSICAL FITNESS AND WELLNESS - Becoming physically fit is a positive health habit that has a major impact on all the dimensions of wellness. It is one area where you can assume control of your lifestyle.
- Aerobic exercise impacts positively on cardiorespiratory endurance, body composition and physical appearance, and psychological benefits.
THE FITT PRESCRIPTION FOR CARDIORESPIRATORY FITNESS - Cardiorespiratory fitness development involves four prescription factors: Frequency, Intensity, Time, and Type of exercise.
"F" EQUALS FREQUENCY - How often should you exercise?
- Exercise three to five times per week with no more than 48 hours between workouts. After 48 hours, the body starts to decondition and lose some of the benefits gained in the last workout.
"I" EQUALS INTENSITY - How hard should you exercise?
- To produce a training effect the American College of Sports Medicine (ACSM) recommends a workout intensity of 60 to 80 percent of your heart rate reserve.
- There are two ways to judge intensity: target heart rate and rate of perceived exertion.
- To determine your target heart rate (THR) range, use the Karvonen equation:
- THR = (maximal heart rate - resting heart rate) X intensity factor + resting heart rate
- Estimation of maximal heart rate = 220 minus age
- Resting heart rate = pulse at complete rest for 1 minute
- Intensity = range of 60% to 80%
- Many people do not check their heart rate during exercise and judge intensity of exercise by rate of perceived exertion (RPE). This is paying attention to how hard or how easy your workout feels. A scale developed by Gunner Borg is used.
"T" EQUALS TIME - How long should each workout be?
- The ACSM recommends a conditioning bout of 20 to 30 minutes at an intensity of 60 to 80 percent not including a warm-up and cool-down.
"T" EQUALS TYPE - What type of exercise promotes aerobic fitness?
- "Aerobic" means "with oxygen". Aerobic activities are those that demand large amounts of oxygen and improve cardiorespiratory endurance.
- These activities are vigorous, continuous, and rhythmic. This includes activities that accelerate respiration and maintain a heart rate in the target range.
- Aerobic dancing, swimming, cycling, walking are all good.
- "Anaerobic" exercise means "without oxygen". Anaerobic activities are high intensity and short duration, such as sprinting. Anaerobic is the opposite of aerobic.
HOW LONG BEFORE RESULTS BECOME APPARENT? - It varies with the individual.
- Measurable differences can occur within 8 to 12 weeks.
THREE PART WORKOUT - A workout includes three parts: a warm-up, a conditioning bout, and a cool-down.
- The warm-up is an important beginning to a workout session and should take 5 to 15 minutes. A task specific activity such as an exercise using the same muscles that will be used in the conditioning bout but at a lowered heart rate level is recommended (i.e., walking or slow jogging before jogging at normal workout intensity)..
- The conditioning bout contains vigorous aerobic exercise that stimulates the cardiorespiraatory system.
- The cool-down is the final segment of the workout. Its purpose is to ease your body back to its resting state. It will take 5 to 15 minutes.
PRINCIPLES OF FITNESS DEVELOPMENT - The beneficial long-term changes that occur with regular exercise depend on several factors. It is important to understand the principles of fitness development:
- Progressive overload is a gradual increase in physical activity, working a muscle group or body system beyond accustomed levels. The key to gradual overload is to adapt the FITT formula to follow the order of FTI (frequency, time, intensity). With time and intensity increase only 10 percent in each per week.
- Specificity means that only the muscles or body systems being exercised will show beneficial changes (to strengthen the cardiorespiratory system, exercise the heart and lungs through aerobic exercise, etc.)
- Reversibility states that changes occurring with exercise are reversible and if a person stops exercising, the body will decondition and adapt to the decreased activity level.
- Individual difference states that people vary in their ability to develop fitness components.
CROSS TRAINING - Cross training involves developing all five health-related components of fitness.
- In the strictest sense, training for a triathlon is not cross training because all three events (swimming, cycling, running) emphasize cardiorespiratory endurance.
- An example of cross training would be to add one swimming session and two weight training workouts to a three-time-per-week jogging program.
ASSESSING PHYSICAL FITNESS - Reasons to assess physical fitness include:
- To identify current fitness levels in several health-related components.
- To determine the effectiveness of current lifestyle in developing fitness.
- To develop an individualized exercise prescription.
- To measure progress toward fitness goals and evaluate effectiveness of the fitness program.
GUIDELINES FOR MEDICAL CLEARANCE - It is safe to begin exercising if you are under 40 years of age for men and under 50 for women, have no health problems, and have had a satisfactory medical checkup in the past 2 years.
- Get medical clearance from a physician if you are over the age guidelines, have health concerns (i.e., diabetic, overweight), sedentary, a smoker, or family members have heart disease risk factors.
PRE TEST INSTRUCTIONS - For any of the cardiorespiratory endurance tests, you will need comfortable clothes appropriate for the activity, and a stopwatch or a watch with a second hand.
- Additional instructions include:
- Avoid taking the test under conditions of extreme heat or cold.
- Do not eat a heavy meal or smoke for up to 3 hours prior to the test.
- Rest from vigorous exercise at least 1 day prior to the test.
- Get adequate sleep the night before testing.
- Warm-up before taking the test and then cool-down after.
- If at any point during the test you begin to feel ill, dizzy, faint, or extremely short of breath, stop!
CARDIORESPIRATORY ENDURANCE TESTS - The best indicator of overall fitness is maximal oxygen uptake (max VO2) which is measured in the laboratory by a treadmill exercise tolerance test or bicycle ergometer. These tests may not be practical or affordable for the average exerciser so one of several field tests may be used.
- Field tests to measure cardiorespiratory endurance include:
- 500 - Yard Water Walk/Run Test
MUSCULAR STRENGTH AND ENDURANCE TESTS - Muscular strength is developed by weight training and is often measured by one maximal lift with weights.
- Muscular endurance can be measured by the following:
- Abdominal Curls (isolates abdominal muscles)
- Push-Ups (isolates arms and upper body muscles)
FLEXIBILITY TESTS - These tests will indicate whether you have a normal range of motion in the lower back and other important areas.
- Quick Checks for Flexibility
BODY COMPOSITION TESTS - These tests are used for determining desirable weight which is calculated for the "trim" category (approximately 12 percent body fat for men and 18 percent body fat for women).
- Body Composition Assessment Using Skinfold Calipers
- Body Girth Measures of Body fat (considerably less accurate than other measures)
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2002 McGraw-Hill Higher Education