Understanding Muscular Deficits of Diabetic Myopathy

The goal of this observational study is to assess if diabetes and obesity are independently related to functional and structural muscle deficits, and how muscular deficits relate to metabolic properties of diabetes and obesity. All studies will include clinical muscle strength and contractile examinations, functional tests, and MR imaging and spectroscopy techniques. The main questions this project aims to answer are: 1. Is chronic hyperglycemia in type 1 and 2 diabetes associated with functional and structural deficits of skeletal muscles unrelated to the presence of neuropathy? 2. Is obesity associated with functional and structural impairments of skeletal muscles unrelated to the presence of type 2 diabetes ? 3. Does weight loss improve muscle metabolic flexibility and economy and modify skeletal muscle function and structure in obese subjects with and without type 2 diabetes? The project will include three studies, intended to answer the hypotheses listed above: Study 1: Evaluation of functional and structural muscular deficits of diabetic myopathy in relation to prolonged hyperglycemia prior to and 6 months following glycemic improvement in patients with type 1 and 2 diabetes Study 2: Functional and structural muscular deficits in severely obese subjects with and without type 2 diabetes prior to assisted weight loss. Study 3: Changes in functional and structural muscle properties following assisted weight loss in severely obese subjects with and without type 2 diabetes - a 1-year follow-up study.