The principal hypothesis of this study is that the micro and macro vasculature of young diabetes mellitus type 1 (DM1) patients is particularly susceptible to atherogenic factors which cause vascular dysfunction at multiple levels of the arterial vasculature and that this dysfunction is demonstrable using state-of-the-art ultrasound methods. The investigators further hypothesize that interventions, such as exercise, that are readily integrated into the daily life of individuals with DM1 can mitigate or reverse these early vascular changes and thereby diminish the otherwise predictable longer-term development of cardiovascular disease (CVD) in type 1 DM