The study proposed here will be the first to assess whether: 1) basal pan-arterial function including myocardial microvascular function is adversely affected by DM1 ; 2) vascular insulin responsiveness in DM1 is impaired as is seen in DM2 3) exercise training or MCR blockade alone or in combination favorably impacts vascular stiffness or NO-induced relaxation in DM1 in the basal state or in response to insulin. This non-invasive vascular profiling provides a functional "biomarker" of pan-arterial health. As such it could be useful for assessing the impact of specific short-term interventions on critical vascular functions in small scale studies (e.g. MCR blockade, statins, GLP-1R agonists) and thereby provide a rationale for selection of candidate therapies for subsequent larger clinical outcome trials. Additionally, non-invasive assessment of pan-arterial function could provide a platform to identify patients for early or more intensive treatment interventions as part of their care plan.