Chapter Exercise and Diabetes Dixie L. Thompson C H A P T E R

Terminology Hyperglycemia Hypoglycemia Insulin Insulin resistance Impaired fasting glucose Impaired glucose tolerance Prediabetes

Common Forms of Diabetes Type 1 Lack of insulin Autoimmune destruction of beta cells of pancreas Genetic link but no known trigger Rely on exogenous insulin Accounts for 5% to 10% of diabetes cases (continued)

Common Forms of Diabetes (continued) Type 2 Generally lifestyle related Obesity Inactivity Genetic predisposition Belonging to an ethnic minority (Hispanic, Native American, African American) Develops over time Generally treated with oral medication; insulin may be required

Diagnosing Diabetes Fasting plasma glucose levels ≥126 mg/dL Abnormal response to oral glucose tolerance test (OGTT): 2-hour plasma glucose ≥ 200 mg/dL Hemoglobin A1c >6.5%

Exercise for Clients With Diabetes Exercise may help reduce the risk of cardiovascular complications Exercise will not prevent or cure type 1 diabetes Exercise improves sensitivity to circulating insulin and glucose tolerance in those with type 2 Regularly active people are 30% to 50% less likely to develop type 2 diabetes

Additional Exercise Benefits for Those With Type 2 Diabetes Weight control Improved lipids Reduction in BP in those who are hypertensive Lower risk of CVD Stress management (stress response induces release of additional glucose, which may be problematic)

Complications of Chronically Elevated Glucose Levels Cardiovascular disease (including CHD) Reduced O 2 delivery Slow healing process Retinopathy Nephropathy Neuropathy

Screening and Testing Clients Medical clearance should be required before moderate or vigorous activity for all clients with any form of diabetes For education on modifying insulin dose or other medications with exercise Diabetes is often considered an equivalent for CHD To screen for existing complications of diabetes (see previous slide) Consideration of graded exercise testing with ECG monitoring

Exercise Prescription for Those With Type 1 or Type 2 Diabetes Frequency 3 days minimum 5 days (to facilitate weight loss in those with type 2) 7 days (to avoid daily fluctuations in glucose levels) Intensity: 50% to 80% HRR or RPE 12 to 16 Duration: 20 to 60 minutes; 10-minute bouts may be used Type: aerobic or resistance training

Resistance Training Guidelines for Those With Type 1 or Type 2 Diabetes Seek physician approval for RT in diabetics with known retinopathy or other contraindications Frequency: 2 or 3 days per week 48- to 72-hour break between muscle groups Intensity: 60% to 80% 1RM (8-12 repetitions) 2 or 3 sets 8 to 10 multijoint exercises

Special Instructions for Type 1 (and type 2 who are new to exercise or do not have adequate glucose control) Modify insulin dose and CHO ingestion under physician guidance to avoid hypoglycemia (and possibly hyperglycemia) Measure glucose 15 minutes before and 15 minutes after exercise If <100 mg/dL, consume 20 to 30 grams of CHO If ≥300 mg/dL (without ketones) moderate intensity only Hydrate well; stop if not feeling well; monitor glucose

Special Instructions for Type 1 (and type 2 who rely on insulin injections) Avoid exercising during peak insulin action See table 20.2 for common forms of insulin Do not inject insulin into areas of active muscle on days of planned exercise Report

General Instructions for All With Diabetes If needed, consume 5 to 30 grams CHO after exercise (especially after vigorous levels) to avoid postexercise hypoglycemia Avoid exercise late at night Extend warm-up and cool-down if needed Supervised exercise is preferred until glucose responses are stable Avoid exercising alone Neuropathy may increase HR and necessitate nonimpact activity

Metabolic Syndrome A group of risk factors that occur together, increasing the risk of cardiovascular disease Diagnosis includes 3 of the following Abdominal obesity High triglycerides (≥150 mg/dL) Low HDL-C Elevated blood pressure: ≥135/≥85, or on medication Elevated fasting glucose: ≥100 mg/dL Up to ¼ of the U.S. adult population may have metabolic syndrome