19 Prescription of Exercise for Health and Fitness chapter

Learning Objectives Understand the importance of a physically active lifestyle for health promotion and disease prevention Discover the importance of obtaining medical clearance before prescribing an exercise program and understand what constitutes the basic components of medical clearance Learn the principles of exercise testing and the exercise electrocardiogram (continued)

Learning Objectives (continued) Review the components of a sound exercise program –Exercise prescription: type of exercise, frequency, duration, and intensity –Methods of monitoring exercise intensity –Components of an exercise program: warm-up and cool-down; endurance, flexibility, and resistance training; and recreational activities Discover how to become more physically active and gain the benefits of regular exercise

Physical Activity Statistics Nearly 40% of the U.S. population >18 years of age report no leisure-time physical activity of light, moderate, or vigorous intensity for at least 10 min Only 22% report engaging in vigorous physical activity sufficient to promote the development and maintenance of aerobic fitness (3 or more days/week, 20 or more minutes) Only 20% report doing physical activity specifically designed to strengthen muscles at least twice a week

The Beginning of the Fitness Revolution Dr. Kenneth H. Cooper

Surgeon General’s Recommendations People of all ages, male and female, benefit from regular physical activity At least 30 minutes of moderate to intense exercise on most days of the week can improve health Additional health benefits are gained through greater amounts of physical activity

Dr. Per-Olof Astrand, Eminent Swedish Physician and Physiologist °

Purpose of Medical Clearance Helps identify potential risk factors Helps to develop an appropriate exercise prescription Helps motivate individuals to know their current blood pressure, body fat, and blood lipid concentrations Provides a baseline to compare changes in health Provides an opportunity to check for early stages of disease

Who Must Receive Medical Clearance Men over 45 Women over 55 Anyone who has risk factors of CAD or cardiopulmonary disease

Graded Exercise Testing Obtained while exercising on a treadmill or cycle ergometer Rate of work is generally increased every 1-3 minutes until maximal work rate is achieved Exercise electrocardiogram is obtained to monitor heart rhythm and electrical conduction abnormalities and to potentially identify existing coronary artery disease Exercise blood pressure is monitored

Obtaining an Exercise ECG © Human Kinetics

Exercise ECG: (a) Normal ECG and (b) an ECG With ST-Segment Depression a b

Major Signs and Symptoms Suggestive of Cardiovascular, Pulmonary, or Metabolic Disease Pain or discomfort in the chest, neck, jaw, arms, or other areas that may be ischemic in nature Shortness of breath at rest or with mild exertion Dizziness or syncope Paroxysmal nocturnal dyspnea Ankle edema Palpitations or tachycardia Intermittent claudication Known heart murmur Unusual fatigue or shortness of breath with usual activities

Graded Exercise Testing Sensitivity: exercise test’s ability to correctly identify individuals who have the disease in question Specificity: test’s ability to correctly identify individuals who do not have the disease in question Predictive value of an abnormal exercise test: accuracy with which abnormal test results reflect the presence of the disease

Medical Evaluation and Clearance Key Points Before beginning an exercise program, men over 45, women over 55, and anyone who is considered to be at a high risk for CAD should have a comprehensive medical evaluation ACSM guidelines should be followed for each phase of the evaluation Exercise ECGs should be conducted for high-risk individuals to detect undiagnosed CAD and other cardiac abnormalities

Components of Exercise Prescription Mode or type of exercise—usually one or more cardiovascular endurance activities Frequency—3 to 5 days per week (or more) Duration—20 to 30 minutes is optimal Intensity—generally at least 50-60% VO 2max, although this varies individually, and health benefits can occur at lower intensities.

Minimum Threshold A minimal threshold for frequency, duration, and intensity must be reached before any aerobic benefits are obtained Threshold varies individually

Training Heart Rate: Linear Relationship Between Heart Rate and VO 2.

Karvonen Method Maximal heart rate reserve = HR max − HR rest Target heart rate (THR) is calculated: THR 75% = HR rest (HR max − HR rest ) Training heart rate ranges can be determined

Metabolic Equivalent (MET) Based on the value of resting metabolic rate 3.5 ml ∙ kg −1 ∙ min −1 = 1.0 MET Useful for a training guideline, but it fails to account for environmental conditions, and it does not allow for changes in physical conditioning

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The Borg Ratings of Perceived Exertion Scale Reprinted, by permission, from G. Borg, Borg's perceived exertion and pain scales (Champaign, IL: Human Kinetics), 47.

The Exercise Program Warm-up and stretching Endurance exercise Cool-down and stretching Flexibility training Resistance training Recreational activities

Warming Up and Cooling Down Involves low-intensity exercise and stretching Warm-up prepares the cardiovascular, respiratory, and muscle systems for more intense exercise Cool-down prevents blood from pooling in the extremities and muscle soreness

Starting a Resistance Training Program Begin with a weight that is one-half of the person’s 1RM This is the proper weight if the person can lift it ~10 times After reaching 15 reps, progress to a heavier weight For weight control: 2-3 sets of each lift per day, 2-3 times per week

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Recreational Activities Important part of any comprehensive exercise program Offer enjoyment and relaxation Can also improve health and fitness

Exercise and Rehabilitation of People With Diseases Cancer Obesity Diabetes Renal disease Osteoporosis Arthritis Chronic fatigue syndrome Fibromyalgia Cystic fibrosis