While insulin-stimulated glucose utilization is impaired in type 2 diabetes, physical exercise results in regular GLUT4 translocation and glucose uptake [2–4], mediated by the activation of 5′-AMP-activated kinase (AMPK), a cellular “fuel sensor” which detects ATP depletion induced by several conditions [3–9]. Here, SLC2A4 is linked to type 2 diabetes mellitus.