desiring to work with healthy and diseased populations. Additional information about certifi cation and licensure opportunities can be found in Chapter 11.
The endorsement of the health benefi ts obtained from physical activity and exercise by the United States Surgeon General in 1996 was a signifi cant milestone in the promotion of physical activity and exercise for healthy and diseased indi- viduals. The Surgeon General’s report highlighted the
positive health effects of physical activity and exercise on the musculoskeletal, cardiovascular, respiratory, and endocrine systems including a reduced risk of pre- mature mortality and reduced risks of coronary heart disease, hypertension, colon cancer, and diabetes mel- litus. Recommendations for the appropriate amount of physical activity and exercise helped establish the standards for using exercise to assist in the treatment of diseased individuals (35).
Throughout the 1990s and early into the twenty fi rst century, government agencies such as the Department of Health and Human Services and the Centers for Disease Control and Prevention established health promotion programs designed to reduce the risk of disease development in healthy individuals and improve the health of those with disease conditions. The National Institutes of Health and other professional organizations such as the American Heart
Association and the American Diabetes Association continue to promote research activities and public health programs designed to improve health and reduce disease risk. As we move further into the twenty fi rst century, additional education and health promotion programs will be instrumental in promoting the use of physical activity and exercise for ensurin g good health
and promoting recovery from disease conditions. Table 4.2 provides a list of the sig- nifi cant events in the historic development of clinical exercise physiology.
exercise to maximize the use of physical activity and exercise for the prevention, management, or rehabilitation of disease. It is also important to understand how different diseases and the medical management of the disease conditions affect the physiologic responses during rest and exercise (25).
Exercise Testing and Evaluation
Exercise testing is an important component of clinical exercise physiology as it is used to clear individuals for safe participation in physical activity and exercise and as a basis for developing an exercise prescription. Diagnostic testing and functional capacity testing are the two broad classifi cations of exercise testing and evaluation.
Diagnostic testing is commonly used to assess the presence of cardiovascular or pulmonary disease. Figure 4.1 illustrates the type of diagnostic exercise test- ing performed by clinical exercise physiologists. If an individual has symptoms of
Table 4.2 Significant Events in the Historic Development of Clinical Exercise Physiology
DATE HISTORIC EVENT
1802 Heberden describes using physical exertion to treat angina pectoris 1854 Stokes recommends using physical activity and exercise during the
recovery from heart disease
1948 Barach promotes the use of physical activity and exercise to promote recovery in individuals with pulmonary disease
1952 Levine and Lown recommend armchair exercises for patients with heart disease
1953 Morris demonstrates a relationship between physical activity and a reduced risk of developing heart disease
1957 Hellerstein and Ford outline a plan for rehabilitation of cardiac patients 1958 Miller and Petty publish a series of papers promoting the use of
physical activity and exercise for treating individuals with chronic pulmonary disorders
1972 and 1975 American Heart Association and the American College of Sports Medicine release textbooks addressing the proper testing and training of healthy and diseased individuals
1974 Publication of the Journal of Cardiac Rehabilitation
1985 American Association of Cardiovascular and Pulmonary Rehabilitation is established
1996 Surgeon General’s report highlights the positive health effects that physical activity has on the physiologic systems and the reduction of chronic disease risk
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heart or lung disease, a history of a possible abnormal cardiac incident, abnormal electric activity of the heart, or a high probability of an underlying disease condi- tion, then diagnostic testing is performed. Exercise tests also help diagnose the presence of heart disease, primarily on the basis of abnormal changes during the test. During exercise, the demands placed on the heart allow abnormal responses and disease conditions to become more readily apparent. Although the clinical exercise physiologist plays an important role in administering the test, only a medical doctor can provide a medical diagnosis of disease (5).
Functional capacity testing provides information about an individu- al’s capacity to participate in physical activity and exercise. The information obtained from testing can be used to prescribe an appropriate physical activity and exercise program to improve fi tness. Functional capacity is usually deter- mined by a submaximal or maximal exercise test that progressively increases in intensity. Functional capacity testing may also be used to determine if an indi- vidual has normal cardiovascular and pulmonary responses to physical activity and exercise (5).
Both diagnostic and functional capacity testing are used to evaluate the car- diopulmonary response to a standard exercise workload. Diagnostic and func- tional capacity tests use workloads that are incremental and are referred to as graded exercise tests (GXT). During a GXT the intensity progresses in stages from light to maximal exertion or to a previously determined ending point. There are general guidelines to be followed when performing a GXT, which is typically con- ducted on a treadmill or a cycle ergometer. Several standard exercise protocols are
FIGURE 4.1 ▼ A diagnostic exercise test.
Diagnostic testing Used to determine a specific disease condition or possible illness.
Functional capacity testing Used to provide an objective measure of an individual’s safe functional abilities.
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available for use and the protocol selected depends on the purpose of the test and the characteristics of the individual being tested (5).
Pretesting Procedures
Physical activity and exercise stress the systems of the body and increase the risk of musculoskeletal injury and abnormal cardiovascular and pulmonary events.
Certain precautions must be taken prior to conducting a diagnostic or functional capacity GXT to reduce the risk of injury or an abnormal event. These precautions include pretesting screening, a physical examination, collection of health history information, and obtaining individual informed consent (5). Clinical exercise physiologists are instrumental in performing some of the pretesting procedures including pretest screening for health risk, collection of health history informa- tion, and acquiring informed consent.
Pretest Screening for Health Risk
Determining if physical activity, exercise, and exercise testing are appropriate for an individual is very important. For most healthy individuals, physical activity and exer- cise do not pose a safety risk if proper exercise techniques and principles are observed.
However, physical activity and exercise may not be safe for everyone, especially if a preexisting medical condition such as cardiovascular, pulmonary, or metabolic disease exists. Some individuals may not be able to participate in exercise testing for specifi c medical reasons. A list of contraindications can be found in the ACSM’s Guidelines for Exercise Testing and Prescription Manual (5). The level of risk for an individual partici- pating in physical activity and exercise must be determined before administering a diagnostic or functional capacity test and the start of an exercise program.
Physical Examination
Certain individuals who are physically inactive and have multiple risk factors for disease require a physician’s referral before they can undergo exercise testing or begin an exercise program. In this situation, the physical examination is designed to assess the risk of an abnormal event while participating in exercise or exercise testing. The ACSM’s Guidelines for Exercise Testing and Prescription Manual can be used to assist clinical exercise physiologists and healthcare professionals in deter- mining the safety of exercise for individuals (5).
Health History
The assessment of an individual’s personal health history and risk factors for car- diovascular disease is an important component of the pretesting screening phase of exercise testing and prescription. The assessment of individual health history is designed to
identify individuals with
• medical contraindications to exercise
identify individuals with clinically signifi cant disease conditions who should be
•
referred to a medically supervised exercise program
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identify individuals with symptoms and risk factors for a disease who should
•
receive further medical evaluation before starting an exercise program identify individuals with special needs for safe exercise participation (e.g.,
•
elderly, pregnant women) (5)
A number of instruments are available for recording and evaluating an individual’s health history. The American Heart Association/ACSM Health/Fitness Prepartici- pation Screening Questionnaire and the Physical Activity Readiness Questionnaire are examples of instruments that can be used in the pretesting screening phase of exercise testing and prescription. Questionnaires should be designed to collect health history information about the individual and his or her family. Figure 4.2 shows an example of a comprehensive health history questionnaire (5).
Informed Consent
Informed consent is a process whereby the individual participating in the exercise test is made aware of and understands the purposes, risks, and benefi ts asso- ciated with the test or exercise program. A signed informed consent should be obtained from an individual prior to diagnostic or functional capacity testing. All of the procedures involved in the exercise test and the potential risks and benefi ts should be thoroughly explained before any testing is done. During the collec- tion of informed consent, participants should be encouraged to ask questions to clarify and resolve uncertainties about the testing procedures. Figure 4.3 shows an example of a comprehensive informed consent document (5).
Performing the Test
After the collection and evaluation of the health history information and the informed consent, the GXT can begin if the individual being tested meets the accepted level of health and disease risk for participation in exercise testing.
Figure 4.4 provides a chart that can be used to identify those individuals who can participate in submaximal or maximal GXT and whether a physician needs to be present during testing. During the GXT, physiologic measures such as resting and exercise heart rate and blood pressure are collected. Additional measures collected often include the rating of perceived exertion (RPE), electric activity of the heart using an electrocardiograph (ECG), oxygen consumption (VO2) to determine maximal oxygen consumption (VO2max), and physical work capacity. A GXT can be either submaximal or maximal depending on the prescreening information and whether the test is for diagnostic or functional capacity assessment (5).
Medical contraindication A condition which makes a particular treatment or procedure inadvisable.
Rating of perceived exertion A subjective assessment of how hard an individual feels he/she is working.
Electrocardiograph An instrument that measures electric potentials on the body surface and generates a record of the electric currents associated with heart muscle activity.
Maximal oxygen consumption The maximal amount of oxygen used by the body during maximal effort exercise.
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Assess your health status by marking all true statements
History You have had:
_____ a heart attack _____ heart surgery _____ cardiac catheterization _____ coronary angioplasty (PTCA) _____ pacemaker/implantable cardiac _____ defibrillator/rhythm disturbance _____ heart valve disease
_____ heart failure _____ heart transplantation _____ congenital heart disease Symptoms
_____ You experience chest discomfort with exertion.
_____ You experience unreasonable breathlessness.
_____ You experience dizziness, fainting, or blackouts.
_____ You take heart medications.
Other health issues _____ You have diabetes.
_____ You have asthma or other lung disease.
_____ You have burning or cramping sensation in your lower legs when walking short distances.
_____ You have musculoskeletal problems that limit your physical activity.
_____ You have concerns about the safety of exercise.
_____ You take prescription medication(s).
_____ You are pregnant.
Cardiovascular risk factors
_____ You are a man older than 45 years.
_____ You are a woman older than 55 years, have had a hysterectomy, or are postmenopausal.
_____ You smoke, or quit smoking within the previous 6 months.
_____ Your blood pressure is 140/90 mm Hg.
_____ You do not know your blood pressure.
_____ You take blood pressure medication.
_____ Your blood cholesterol level is 200 mg/dL.
_____ You do not know your cholesterol level.
_____ You have a close blood relative who had a heart attack or heart surgery before age 55 (father or brother) or age 65 (mother or sister).
_____ You are physically inactive (i.e., you get 30 minutes of physical activity on at least 3 days per week).
_____ You are 20 pounds overweight.
If you marked any of these statements in this section, consult your physician or other appropriate health care provider before engaging in exercise.
You may need to use a facility with a medically qualified staff.
If you marked two or more of the statements in this section you should consult your physician or other appro- priate health care provider before engaging in exercise. You might bene- fit from using a facility with aprofes- sionally qualified exercise staff†to guide your exercise program.
_____ None of the above You should be able to exercise safely
without consulting your physician or other appropriate health care provider in a self-guided program or almost any facility that meets your exercise program needs.
*Modified from American College of Sports Medicine and American Heart Association. ACSM/AHA Joint Position Statement: Recommendations for cardiovascular screening, staffing, and emergency policies at health/fitness facili- ties. Med Sci Sports Exerc. 1998:1018.
†Professionally qualified exercise staff refers to appropriately trained individuals who possess academic training, practical and clinical knowledge, skills, and abilities commensurate with the credentials defined in Appendix F.
FIGURE 4.2 ▼ Comprehensive health history questionnaire (5). (From ACSM’s Guidelines for Exercise Testing and Prescription. 8th ed. Philadelphia (PA): Lippincott, Williams & Wilkins; 2009.)
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Informed Consent for an Exercise Test Purpose and Explanation of the Test
You will perform an exercise test on a cycle ergometer or a motor-driven treadmill. The exercise intensity will begin at a low level and will be advanced in stages depending on your fitness level. We may stop the test at any time because of signs of fatigue or changes in your heart rate, ECG, or blood pressure, or symptoms you may experience. It is important for you to realize that you may stop when you wish because of feelings of fatigue or any other discomfort.
Attendant Risks and Discomforts
There exists the possibility of certain changes occurring during the test. These include abnormal blood pressure, fainting irregular, fast or slow heart rhythm, and in rare instances, heart attack, stroke, or death. Every effort will be made to minimize these risks by evaluation of preliminary information relating to your health and fitness and by careful observations during testing. Emergency equipment and trained personnel are available to deal with unusual situations that may arise.
Responsibilities of the Participant
Information you possess about your health status or previous experiences of heart-related symptoms (e.g. shortness of breath with low-level activity, pain, pressure, tightness, heaviness in the chest, neck, jaw, back, and/or arms) with physical effort may affect the safety of your exercise test. Your prompt reporting of these and any other unusual feelings with effort during the exercise test itself is very important. You are responsible for fully disclosing your medical history, as well as symptoms that may occur during the test. You are also expected to report all medications (including nonprescription) taken recently and, in particular, those taken today, to the testing staff.
Benefits to Be Expected
The results obtained from the exercise test may assist in the diagnosis of your illness, in evaluating the effect of your medications or in evaluating what type of physical activities you might do with low risk.
Inquiries
Any questions about the procedures used in the exercise test or the results of your test are encouraged. If you have any concerns or questions, please ask us for further explanations.
Use of Medical records
The information that is obtained during exercise testing will be treated as privileged and confidential as described in the Health Insurance Portability and Accountability Act of 1996. It is not to be released or revealed to any person except your referring physician without your written consent. However, the information obtained may be used for statistical analysis or scientific purposes with your right to privacy retained.
Freedom of Consent
I hereby consent to voluntarily engage in an exercise test to determine my exercise capacity and state of cardiovascular health. My permission to perform this exercise test is given voluntarily. I understand the I am free to stop the test at any point if I so desire. I have read this form, and I understand the test procedures that I will perform and the attendant risks and discomforts. Knowing these risks and discomforts, and having had an opportunity to ask questions that have been answered to my satisfaction, I consent to participate in this test.
Date Signature of Patient
Date Signature of Witness
Date Signature of Physician or Authorized Delegate 1.
2.
3.
4.
5.
6.
7.
FIGURE 4.3 ▼ A comprehensive informed consent document. (From ACSM’s Guidelines for Exercise Testing and Prescription. 8th ed. Philadelphia (PA): Lippincott, Williams & Wilkins; 2009.)
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Heart Rate
Resting heart rate is usually measured after the individual has been sitting quietly for 5 minutes or longer. An electronic heart rate monitor is often used to obtain heart rate in healthy individuals. In all clinical settings, however, the heart rate is determined from the ECG recordings or directly off the digital display of the oscilloscope. Many factors can infl uence the resting and exercise heart rate including smoking, caffeine ingestion, fever, high humidity, stress, food digestion, certain medications, and prior physical activity or exercise. That is why pretesting instructions to individuals often prohibit the use of caffeine, food consumption, or activity prior to exercise testing. During exercise, the heart rate is recorded peri- odically to ensure an appropriate cardiovascular response to exercise and for later use in developing an exercise prescription (5).
Blood Pressure
Blood pressure is measured after a period of quiet sitting and often at the same time as the resting heart rate. Blood pressure is the force exerting pressure against the walls of the blood vessels in the circulatory system. The highest pressure recorded during a cardiac cycle (one heart beat to the next heart beat) occurs during the contraction phase (systole) of the left ventricle and is called the systolic blood pres- sure. A measurement of systolic blood pressure provides an estimation of the work of the heart, as well as the pressure exerted against the walls of the blood vessels. The period between heart beats is called the relaxation phase of the heart (diastole) and the pressure recorded during this period is called the diastolic blood pressure. Dur- ing diastole, the blood pressure is decreased and this measurement gives an indirect indication of the ease with which blood fl ows through the circulatory system (5).
Blood pressure is an important indicator of overall health. When resting blood pressure is chronically elevated, a disease condition called hypertension
Risk Stratification
Low Risk Asymptomatic
≤ 1 Risk Factors
Moderate Risk Asymptomatic
≥ 2 Risk Factors
High Risk Symptomatic, or known cardiac, pulmonary, or
metabolic disease
Medical Exam & GXT before exercise?
Mod Ex - Not Nec Vig Ex - Not Nec
Medical Exam & GXT before exercise?
Mod Ex - Not Nec Vig Ex - Rec
Medical Exam & GXT before exercise?
Mod Ex - Rec Vig Ex - Rec
MD Supervision of Exercise Test?
Submax - Not Nec Max - Not Nec
MD Supervision of Exercise Test?
Submax - Not Nec Max - Rec
MD Supervision of Exercise Test?
Submax - Rec Max - Rec
Mod Ex:
Vig Ex:
Not Nec:
Rec:
Moderate intensity exercise; 40-60% of VO2max; 3-6 METs; “an intensity well within the individual’s capacity, one which can be comfortably sustained for a prolonged period of time (~45 minutes)”
Vigorous intensity exercise; > 60% of VO2max;
> 6 METs; “exercise intense enough to represent a substantial cardiorespiratory challenge”
Not Necessary; reflects the notion that a medical examination, exercise test, and physician supervision of exercise testing would not be essential in the preparticipation screening, however, they should not be viewed as inappropriate
Recommended; when MD supervision of exercise testing is “Recommended,” the MD should be in close proximity and readily available should there be an emergent need
•
•
FIGURE 4.4 ▼ Exercise testing and testing supervision recommendations based on risk factor stratification. (From ACSM’s Guidelines for Exercise Testing and Prescription. 8th ed. Philadelphia (PA): Lippincott, Williams & Wilkins; 2009.)
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