Alex Gustafson

Introduction: Type 2 Diabetes Mellitus (T2D) is a chronic disease characterized by insulin resistance, systemic inflammation, and impaired GLUT-4 translocation¹. T2D has become epidemic in the U.S. as 1/3 of the population is diabetic or pre-diabetic². These Americans are susceptible to major hyperglycemic related consequences such as strokes, heart attacks, kidney failure, amputations, and blindness¹. Current pharmacological treatments do not cure or maintain glucose levels long-term. Currently, The American Diabetes Association recommends 150 minutes of moderate-intensity training (MIT) per week for prevention and therapy of T2D. However, high intensity interval training (HIIT) is an emerging program that could effectively reduce T2D prevalence and morbidity³.    Methods: Thirty eight human subjects with T2D were split into a MIT or HIIT group in a non-randomized fashion to equalize age and physical activity level. MIT group trained at 70-85% heart rate continually walking while the HIIT group trained with 4 minute intervals at 85-95% heart rate running up a hill. HbA1C, insulin sensitivity with HOMA-IR, and VO_2max were measured before and after the intervention and compared³. In the mouse model, MIT and HIIT were compared to additionally compare glucose metabolism using measures of GLUT-4 with Western blot analysis⁴.  Results: Percentage of muscle mass stimulated and intensity determines metabolic response. The HIIT group decreased HbA1c levels by .58% (p<.001) while the MIT group had no change. The .58% HbA1C reduction represents an overall 8-10% risk reduction of cardiovascular events. The HIIT group increased absolute VO_2max by 19% while the MIT group showed no change³. Those in moderate to vigorous programs, but not mild, had decreased incidence of major cardiovascular events and death within 5 years⁵. In mice, GLUT-4 content increased 2 fold (p<.05) in HIIT as compared to MIT⁴.  Conclusions: HIIT shows superior results in glycemic control, glycemic metabolism, and reduction in major cardiovascular related events. This program is time efficient, has increased long-term patient adherence, and more effectively targets T2D metabolic dysfunction.

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