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Chapter 2 Pre-Exercise Evaluation and Assessment
A safe and effective exercise program for people with diabetes minimizes the acute risks and long-term complications associated with physical activity while maximizing the benefits (Bernbaum 1989, Gilchrist 2000, Seeger 2011). As the benefits frequently outweigh the risks, regular participation in a variety of physical activities should be recommended and encouraged for almost all individuals with diabetes, keeping in mind that certain comorbidities (whether diagnosed or not) may carry a higher risk than others.
Case in Point: Pre-Exercise Screening, Cardiovascular Risk, and Disease Detection
AB is a 58-year-old man who has had type 2 diabetes (T2D) for ~10 years and is interested in starting a new exercise training program at a local community center. The exercise that he intends to do revolves around a program of aerobic exercise on a treadmill at an intensity equal to ~75% of his heart rate reserve (see chapter 4 for more information on prescribing exercise intensity), which is considered a vigorous physical activity—that is, more intense than his normal daily walking pace (i.e., brisk walking). Although he has engaged in several exercise training programs off and on over the past few years, his most consistent physical activity currently is playing golf on most weekends (which includes walking and carrying his clubs). His only medications are metformin (used to control morning hyperglycemia) and a lipid-lowering drug to reduce cholesterol levels.
Questions to Consider
1. Should AB schedule an appointment with his primary physician or other health-care provider for a pre-exercise medical evaluation and examination?
2. Does AB need to undergo a graded exercise stress test before participation in his planned exercise intensity?
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MEDICAL SCREENING AND EXAMINATION
Ideally, most individuals diagnosed with diabetes should consult a health-care provider before beginning an intense physical fitness program (Colberg 2010, 2011). An absolute requirement to do so before participation in all types of physical activity should not be uniformly enforced, however, as it may prevent individuals from gaining any of the health and psychological benefits associated with being normally physically active, such as undertaking brisk walking as part of their activities of daily living.
Screening for Diabetes-Related Complications
Given that exercise participation can be complicated by the presence of diabetes-related health complications (Sigal 2004), before undertaking new higher-intensity physical activity, individuals are strongly advised to undergo a detailed medical evaluation and screening for acute and chronic blood glucose control, physical limitations, medications, and macrovascular and microvascular complications associated with the heart, blood vessels, eyes, kidneys, feet, and nervous system (Colberg 2010). A medical examination conducted before undertaking a new physical activity or fitness program can include determination of the presence of diabetes-related (or other) comorbidities (e.g., cardiovascular disease, neuropathy, nephropathy, and retinopathy) that can affect an individual’s ability to undertake certain types of physical training, increase cardiovascular risk, or predispose them to injuries (Sigal 2004, 2006; Colberg 2010). Certain conditions may be contraindicated or predispose individuals to injury, such as uncontrolled hypertension, severe autonomic neuropathy, severe peripheral neuropathy or history of foot lesions, and unstable proliferative retinopathy. The individual’s age and previous physical activity level also should be considered (American Diabetes Association [ADA] 2013). Such health considerations should be factored into an exercise prescription for it to be both safe and effective.
Physical Examination
Minimally, starting body weight, heart rate, and resting blood pressure ideally should be assessed before exercise participation. In addition, inspection of the lower extremities for edema and the presence of arterial pulses is recommended, along with tests of neurological function, especially if the individual has prescribing prior bouts of dizziness or faintness during or following physical exertion. Given that such symptoms could result from any number of conditions, including autonomic dysfunction, cardiovascular insufficiency, medication use, or dehydration, among others, a determination of the cause (if possible) is helpful in prescribing appropriate physical activity regimens. Likewise, a visual inspection of the feet and lower extremities can reveal any contraindications to weight-bearing exercise, including unhealed ulcerations. A history of falls is also clinically relevant, given that certain exercise interventions like balance training have been shown to lower the risk of falling in people with T2D (Morrison 2010). Finally, the health-care or fitness professional should be made aware of any orthopedic or other limitations (like prior joint surgery) that might affect exercise prescription