Polycystic Ovary Syndrome (PCOS) affects 10% of all women, and it usually co-exists with high levels of male pattern hormones (also termed androgens). Women with PCOS are at increased risk of metabolic complications such as diabetes, non-alcoholic fatty liver disease, high blood pressure and heart disease. However, very little is understood about how androgen excess results in increased metabolic complications observed in women with PCOS. The main aims of the REFUEL PCOS study are to compare markers of energy metabolism in women with PCOS to those without PCOS. This will allow the investigators to better understand metabolic risk by examining the relationship between androgen excess and energy metabolism. Skeletal muscle is an important site of energy metabolism, and emerging theories are that androgen excess impairs skeletal muscle energy balance and increases the risk of complications. Based on these emerging theories, the investigators want to investigate the effects of androgens on muscle energy metabolism. The investigators will also examine whether certain blood and urine result patterns can help identify differences in muscles energy metabolism and which women are at the highest risk of metabolic complications. This research will give insight into the metabolic risk associated with PCOS and treat and, where possible, prevent the development of metabolic disease in affected women.