- For this study they enrolled 25–50 years old vitamin D deficient T2DM patients.
- Participants performed moderate intensity aerobic exercise for 3–months and were randomized to receive simvastatin 40 mg per day, simvastatin 40 mg daily and vitamin D 60,000 units once weekly, or vitamin D 60,000 units once weekly.
- The primary results were cardiorespiratory fitness (peak oxygen consumption) and skeletal muscle mitochondrial content (citrate synthase activity in vastus lateralis muscle).
- A sum of 28 patients finished the study.
- Cardiorespiratory fitness reduced by 8.4% (p < 0.05) following 3 months of simvastatin therapy.
- Vitamin D supplementation blunted the decline in cardiorespiratory fitness to 0.6% (p < 0.05 for between–group difference in change from baseline).
- Similarly, skeletal muscle mitochondrial content reduced by 3.6% with simvastatin however enhanced by 12.1% on supplementation with vitamin D, although the between– group difference was insignificant.
- Vitamin D alone expanded cardiorespiratory fitness and mitochondrial content by 7.1% (p < 0.05) and 16.7% respectively.