Insulin resistance is a disorder of the body's endocrine system that affects up to 80 million Americans, according to the American Academy of Family Physicians. Treatment primarily involves lifestyle changes, including exercise. You don't have to run marathons to decrease or reverse insulin resistance -- it's just important that you engage in some form of physical activity.
Identification
If you have insulin resistance, your body's muscle, fat and liver cells don't respond normally to insulin. This requires your pancreas to produce more insulin to help glucose enter cells, where it's used as energy. Excess glucose builds up in your bloodstream and can lead to diabetes. Although there are often no symptoms, you may have a condition called acanthosis nigricans, which causes dark patches of skin on various parts of your body. Insulin resistance can be diagnosed with a test called the euglycemic insulin clamp technique or by taking readings of fasting insulin levels.
Significance
Left untreated, insulin resistance can cause not only diabetes but also obesity, high cholesterol and cardiovascular disease. Although medical experts believe genetics may make you more susceptible to the condition, being overweight and sedentary also increases your risk, according to the National Institutes of Health. Regular physical activity, such as daily walking, can substantially decrease insulin resistance.
Expert Insight
A study at the University of South Carolina School of Public Health led by E.J. Mayer-Davis followed almost 1,500 patients over a year who exercised five times a week. The results, published in "The Journal of the American Medical Association" in March 1998, found that increased participation in any activity, nonvigorous or vigorous, was associated with significantly decreased levels of insulin sensitivity.
In June 2007, Simon Schenk and Jeffrey Horowitz from the University of Michigan reported in "The Journal of Clinical Investigation" that a single session of exercise on a treadmill markedly improved insulin sensitivity in healthy, nonobese women by reducing toxic fatty acid metabolism and also led to increased whole-body fatty acid oxidation for at least 16 hours afterward. The researchers concluded that regular exercise could help reduce insulin resistance in obese people.
Prevention/Solution
The National Institutes of Health notes that the Diabetes Prevention Program and other large studies have demonstrated that if people with insulin resistance cut fat and calorie intake and increase their physical activity to five days a week, they can delay or entirely prevent the onset of diabetes and even see their blood glucose levels return to normal. The American Academy of Family Physicians says that even moderate physical activity for 30 minutes a day can substantially decrease insulin resistance.
Warning
You should consult with your health care provider before starting a new exercise program. MayoClinic.com recommends assessing your fitness level first, allowing time for recovery between sessions and breaking your workouts into shorter, more frequent sessions if needed. Stop exercising if you experience pain, shortness of breath, dizziness or nausea.
References
- National Diabetes Information Clearinghouse: Insulin Resistance
- American Academy of Family Physicians: Insulin Resistance Syndrome
- "The Journal of Clinical Investigation": Acute exercise increases triglyceride synthesis in skeletal muscle and prevents fatty acid--induced insulin resistance; Simon Schenk and Jeffrey F. Horowitz; June 2007
- PubMed.gov: Intensity and amount of physical activity in relation to insulin sensitivity
- "Archives of Internal Medicine": Effects of Exercise Modality on Insulin Resistance and Functional Limitation in Older Adults; Lance E. Davidson et al.; January 2009
