Edinburgh Napier University

  The aim of this study was to investigate if there was a synergistic effect of high intensity intermittent training (HIIT) and vitamin D3 supplementation on glycaemic control. Twenty participants (age, 34±9y; BMI, 31.4±2.8 kg·m-2) completed 6 weeks HIIT, were randomised to ingest 100 µg/day of 25-hydroxyvitamin D3 or placebo, with response to an oral glucose tolerance test (OGTT) determined at baseline and 72h post-intervention. Glucose (P=0.027) and insulin (P=0.017) concentrations were reduced during the OGTT, as was glucose and insulin AUC (P=0.043; P=0.049). Decreases in waist and hip circumference (P=0.019; P=0.002) and systolic BP (P=0.004) were observed. Supplementation increased 25-hydroxyvitamin D3 by 120 % to a sufficiency status (P<0.001), although this did not proffer additional effects on metabolic health. Thus, six weeks of HIIT improved glycaemic control in overweight and obese adults, highlighting the potential for HIIT to reduce the risk of developing type 2 diabetes.