A moderate aerobic exercise program without weight loss could possibly improve insulin sensitivity in both lean and obese sedentary adolescents. Atleast this is what scientists from Baylor College of Medicine have to say. This novel study seems to isolate the impact of exercise from diet and weight loss interventions.
Insulin is known to be a hormone produced in the pancreas which allows glucose to enter the cells. Supposedly, glucose can be used for energy or stored for future use by the body.
In order to maintain normal blood sugar levels, obese adolescents are required to increase their production of insulin. The production of insulin could be increased as these adolescents seem to be resistant to insulin.
However, increased insulin production apparently places higher demands on the pancreas. These higher demands could perhaps weaken pancreatic beta cells to the point that they would be unable to produce adequate amounts of insulin thereby causing an imbalance in blood sugar levels. Eventually this seems to lead to type 2 diabetes.
Senior author of the study, Agneta Sunehag, MD, PhD, of Baylor College of Medicine stated that, “Because weight loss can be difficult to achieve and maintain in obese sedentary children, the purpose of this study was to determine whether a controlled exercise program, without any diet intervention and with no intention of weight loss, would improve fat distribution and sensitivity to insulin. We found that a 12-week moderate aerobic exercise program consisting of four 30-minute workouts a week increased fitness and improved insulin sensitivity in both lean and obese adolescents.”
During the study, experts provided the 12-week moderate aerobic exercise program to approximately 29 adolescents in which 14 were lean and 15 obese.
During the exercise sessions, subjects were noted to have worked out on a treadmill, elliptical or bicycle. Supposedly, the goal of each exercise session was to get the participants’ heart rate to increase to at least 70 percent of their maximum capability. Glucose and insulin concentrations were believed to have been measured both before and after the exercise program.
Evidently, cardiovascular fitness was determined using an oxygen consumption test. This test is known to consist of calculating oxygen uptake of the participant during a treadmill exercise. During this test, speed and incline appears to get increased every three minutes until the subject reaches his maximum exercise capacity.
Sunehag claimed that numerous studies comprises both diet and exercise interventions which seems to make it difficult in determining which intervention is most effective and best accepted by adolescents.
On the other hand, the findings of this study revealed that exercise alone could increase fitness and improve insulin sensitivity thereby making an aerobic program a probable useful tool in preventing obesity-related illnesses.
The findings of the study will be published in The Endocrine Society’s Journal of Clinical Endocrinology and Metabolism (JCEM).