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. 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.
Ideally, most individuals diagnosed with diabetes should consult a health-care provider before beginning an intense physical fitness program (1). 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.
Given that exercise participation can be complicated by the presence of diabetes-related health complications (2), 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 (1). 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 (1,2,3). 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 (4). Such health considerations should be factored into an exercise prescription for it to be both safe and effective.
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 experienced 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 determining 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 type 2 diabetes (T2D) (5). 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 for the individual.
For individuals who wish to participate in low-intensity activities like walking, physicians and other health-care providers should use clinical judgment in deciding whether to recommend pre-exercise testing (1). Conducting exercise stress testing before walking that does not exceed the cardiovascular demands of an individual’s usual activities of daily living may not be routinely necessary as a diagnostic tool for cardiovascular disease, and requiring it may create barriers to participation in all physical activities. Moreover, current guidelines avoid automatic inclusion of lower risk individuals in graded exercise testing requirements, given that their risk of a false-positive test is higher and may outweigh the benefits of detection of cardiovascular abnormalities (6).
For exercise more vigorous than brisk walking or exceeding the demands of everyday living, it remains unclear whether sedentary and older individuals with type 1 diabetes (T1D) or T2D will benefit from undergoing graded exercise testing or other types of routine cardiovascular testing (7). Depending on the individual’s age, diabetes duration, and presence of additional cardiovascular risk factors or diabetes-related complications, however, the risks associated with conducting such testing may be justified when it can reveal underlying pathologies that potentially affect either the safety or efficacy of more intense exercise participation.
The prevalence of symptomatic and asymptomatic coronary artery disease is greater in individuals with T2D (8), and maximal graded exercise testing can identify a small proportion of asymptomatic people with severe coronary artery obstruction (9). Although the latest ADA Standards of Medical Care state that the need for screening asymptomatic diabetic patients for coronary artery disease remains unclear (4,7), graded exercise stress test with electrocardiogram (ECG) may be indicated for diabetic individuals to detect cardiovascular disease based on the criteria in the table that follows (1). Providers should use clinical judgment in this area. Certainly, high-risk patients should minimally be encouraged to start physical activity participation with short periods of low-intensity exercise and to increase the intensity and duration slowly.
Table. Criteria for Recommending Graded Exercise Stress Testing
|Age >40 years, with or without cardiovascular disease risk factors other than diabetes|
|Age >30 years and:
|Any of the following, regardless of age
In summary, for most people with diabetes, low-level physical activities can be undertaken without the need for a medical exam or graded exercise test that potentially could create barriers to participation. In some cases, however, higher risk individuals desiring to undertake moderate- or vigorous-intensity exercise training may benefit from undergoing a medical evaluation and possible stress testing with ECG before participation to diagnose pre-existing cardiovascular problems that may make such training more risky.
- Colberg, S. R., R. J. Sigal, B. Fernhall, J. G. Regensteiner, B. J. Blissmer, R. R. Rubin, L. Chasan-Taber, A. L. Albright, B. Braun, American College of Sports Medicine, and Association American Diabetes: Exercise and type 2 diabetes: the American College of Sports Medicine and the American Diabetes Association: joint position statement. Diabetes Care 33 (12):e147–e167, 2010
- Sigal, R. J., G. P. Kenny, D. H. Wasserman, and C. Castaneda-Sceppa: Physical activity/exercise and type 2 diabetes. Diabetes Care 27 (10):2518–2539, 2004
- Sigal, R. J., G. P. Kenny, D. H. Wasserman, C. Castaneda-Sceppa, and R. D. White: Physical activity/exercise and type 2 diabetes: a consensus statement from the American Diabetes Association. Diabetes Care 29 (6):1433–1438, 2006
- American Diabetes Association: Standards of Medical Care in Diabetes 2013. Diabetes Care no. 36 (Suppl. 1):S11–S66, 2013
- Morrison, S., S. R. Colberg, M. Mariano, H. K. Parson, and A. I. Vinik: Balance training reduces falls risk in older individuals with type 2 diabetes. Diabetes Care 33 (4):748–750, 2010
- Colberg, S. R., and R. J. Sigal: Prescribing exercise for individuals with type 2 diabetes: recommendations and precautions. Phys Sportsmed 39 (2):13–26, 2011
- Bax, J. J., L. H. Young, R. L. Frye, R. O. Bonow, H. O. Steinberg, and E. J. Barrett: Screening for coronary artery disease in patients with diabetes. Diabetes Care 30 (10):2729–2736, 2007
- Kothari, V., R. J. Stevens, A. I. Adler, I. M. Stratton, S. E. Manley, H. A. Neil, and R. R. Holman: UKPDS 60: risk of stroke in type 2 diabetes estimated by the UK Prospective Diabetes Study risk engine. Stroke 33 (7):1776–1781, 2002
- Curtis, J. M., E. S. Horton, J. Bahnson, E. W. Gregg, J. M. Jakicic, J. G. Regensteiner, P. M. Ribisl, J. E. Soberman, K. J. Stewart, M. A. Espeland, and Look Ahead Research Group: Prevalence and predictors of abnormal cardiovascular responses to exercise testing among individuals with type 2 diabetes: the Look AHEAD (Action for Health in Diabetes) study. Diabetes Care 33 (4):901–907, 2010
In addition, anyone wishing to earn free CME credits through the ADA for completing a new self-assessment program on exercise and diabetes may do so now through the ADA’s web site at http://professional.diabetes.org/ce.
Copyright © 2013 Diabetes In Control, Inc.