Preventing Insulin Resistance is the New Fitness Trend

Science Favors Exercise to Improve Insulin Resistance

A current review released July 2015 by the Journal of Obesity and Weight Loss has provided interesting feedback about insulin resistance. Insulin resistance and sensitivity are a growing concern in the United States and fixing it may soon be the top fitness goal even over weight loss. Without mastering our insulin levels, the ability to lose weight or fat remains a struggle. Before diving into the nuts and bolts of the findings, it is important we understand what insulin is and how insulin resistance affects our body.

What is Insulin?

Insulin Resistance
Insulin Helps Our Body Absorb Glucose for Energy. tbradford E+/Getty Images

Insulin is a hormone released by our pancreas (an organ located behind the stomach) and plays a large role in how our body uses food for energy (metabolism). When we eat carbohydrates our digestive processes go to work breaking down the food into a form of sugar called glucose that enters our bloodstream.  Insulin then has the job of grabbing the glucose and helps our body absorb it into our cells to create usable energy. Insulin also has the role of lowering blood glucose (sugar) levels, storing excess glucose (glycogen), and reducing blood glucose levels in our liver.

What is Insulin Resistance?

Insulin Resistance
Insulin Resistance Builds Glucose in the Bloodstream. BSIP/UIG Universal Images Group/Getty Images

Insulin resistance occurs when the “body produces insulin but does not use it effectively.” Instead of our cells being able to absorb the glucose released in the bloodstream, it continues to build up in the blood leaving our cells without energy. This causes an ugly reaction of our body compensating and dumping more insulin to create more glucose in an effort to fix the problem. This buildup over time creates conditions like prediabetes and type-2 diabetes and unfortunately many people don’t realize insulin resistance is happening until they are hit with this news. When insulin hormone is unable to function right, we are unable to metabolize fat or lose weight efficiently in addition to being at risk for disease. Let’s take a look at what the current study has to say about insulin resistance and their recommendations.

Understanding the Research

Insulin Resistance
Being Overweight Contributes to Insulin Resistance. Kathy Konkle DigitalVision Vectors/Getty Images

The purpose of the research was to clarify past studies on insulin resistance and provide a more accurate assessment of methods to improve the condition. It appears prior findings have been “overly simplistic and even misleading.” The introduction discusses how insulin resistance is no longer isolated to older adults, but now includes people of all ages, and those who are middle-aged, overweight and sedentary. Being overweight with a body mass index (BMI) over 25 and obese with a BMI rating over 30 are risk factors contributing to reduced glucose function but insulin resistance is not quite that simply defined according to the research. Having more subcutaneous (under the skin) and abdominal fat also contribute to insulin malfunction and inability to suppress glucose overproduction. Our bodies are manufacturing too much sugar, collecting too much fat and keeping us in a constant state of inflammation.

The research was conducted over a 2-year period with 978 publications studied and ultimately 158 accepted after critical review of subjects meeting the following criteria: 30 years of age or older, overweight to obese, free of disease, not taking hormone replacement therapy or medications affecting metabolism, and non-smoker. Base-line scores for insulin resistance were established through clinical methods and an important part of determining more accurate results. The goal of the research was to determine if exercise alone or with a caloric deficit improved insulin resistance.

The Bottom Line

Insulin Resistance
Insulin Resistance is Improved by Exercise and Eating Right. webphotographeer E+/Getty Images

Although insulin resistance is significantly improved with weight loss achieved through caloric reduction, there is something lacking that only exercise can provide. It appears greater body functioning after weight loss with exercise not only improved “insulin stimulated glucose disposal” but also stimulated increased cellular fat burning. “Sustained improvements in glucose metabolism may be influenced by exercise intensity as it relates to changes in body composition.” Changing up the diet to lose weight does show a decrease in adipose tissue (fat) but “does not influence muscle metabolism similar to exercise training.” The bottom line still recommends incorporating both a healthy diet and exercise program as powerful tools proven to improve glucose metabolism and insulin resistance.

Sources

Journal of Obesity and Weight Loss, Exercise Training and Insulin Resistance: A Current Review, Tyler E Keshel et al., 7/30/15

Journal of Diabetes Complications, Prevalence and trends of insulin resistance, impaired fasting glucose, and diabetes, Ioannou GN et al., 12/07

National Institute of Diabetes and Digestive and Kidney Diseases, Insulin Resistance and Prediabetes, George A. Bray, M.D et al., 6/14

Sports Medicine, Insulin resistance with aging: effects of diet and exercise, Ryan AS, 11/00

National Institute of Diabetes and Digestive and Kidney Diseases, Insulin Resistance and Prediabetes, 6/2014

American Diabetes Association, Exercise and Type 2 Diabetes, The American College of Sports Medicine and the American Diabetes Association: joint position statement, Sheri R. Colberg et al., 12/10

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