PPARD and type 2 diabetes mellitus: PPARδ expression is upregulated in skeletalmuscle of T2D subjects and high-fat fed rats after bouts of exercise [46, 51–54] and may play a role in providinga continuous source of energy to support the increasing energy demand.Consistent with this hypothesis, skeletal muscle overexpression of PPARδ was associated with significant muscle-typeswitching from glycolytic to oxidative fibers, further supporting its role inlipid oxidation [55].