 However, the discovery that athletes as well as obese individuals have high IMTG levels confounded these findings.Instead, IMTG metabolites, such as diacylglycerol and ceramide are responsible for the insulin resistance.Studies demonstrating the effects of IMTGs show that the mechanism involves the activation of the protein kinase C theta, which promotes the phosphorylation of IRS-1, thereby inhibiting the insulin signaling cascade.