Abstract

Introduction: The Framingham Risk Score was developed to determine the likelihood of developing cardiovascular disease (CVD) in the next 10 years using an individual’s age, gender, total cholesterol (TC), High Density Lipoprotein Cholesterol (HDL-C), smoking habits, and systolic blood pressure (SBP). Run-Sprint Interval Training (R-SIT) has shown improvements in various health and blood markers while reducing total exercise time. To date there has not been a study that examines the effects of R-SIT and Moderate Intensity Training (MIT) on Framingham Risk. The purpose of this study was to determine if a reduction of the 10-year risk of CVD (determined by Framingham CVD risk calculator), is greater in an R-SIT experimental group compared to a moderate intensity group (MIT) of sedentary prediabetic women, after a 16-week intervention.

Methods: Twenty-five sedentary prediabetic women were randomized into R-SIT (n=6) or MIT (n=9) groups and required to attend 3 weekly training sessions and 1 weekly Diabetes Prevention Program session for 16-weeks. During the first 4 weeks, R-SIT performed 4x30s maximal sprints on a treadmill at a self-selected speed and incline, followed by a 4-min active recovery between intervals. Intervals increased by 2 every 4 weeks. MIT walked continuously at 45-55% Heart Rate Reserve for 30-mins during the first 4 weeks, and increased by 10-mins every 4 weeks. FRS markers were measured at baseline, mid, and post intervention.

Results: After 16-weeks of exercise training, all participants saw significant reductions from baseline to post testing in weight (49.01±14.14, 47.15±13.65 kg, respectively) and BMI (49.51±10.78, 39.71±10.22 kg/m2, respectively), with R-SIT participants exercising less total time. MIT saw significant within group decreases for weight (-2.60±1.32 kg) and BMI (-2.42±1.32 kg), while R-SIT observed a decrease in BMI (-0.85±0.06 kg/m2) with trending significance (p=.078). Additionally, R-SIT participants observed significant changes in TGs (124.17±59.64, 101.33±25.44 mg/dL, respectively) from midline to post. Though FRS was significantly different between groups at all three time points, there was no significant within group changes observed. 

Conclusion: Though previous R-SIT studies have suggested improved body composition and cardiovascular risk factors when compared to MIT, the present study only observed significant changes in body composition and minimal changes to CVD risk factors. Additional research is needed to further understand the effects of interval training on blood lipid profiles and its relationship with CVD, especially in the clinical population.