Impact of Semaglutide (Ozempic/Wegovy®) on Heart and Muscle Mass

The aim of this study is to use advanced MRI scans to track changes in both muscle and fat in the body and heart over a 12-month period in individuals starting semaglutide. By doing so, we hope to gain a clearer understanding of how semaglutide affects muscle health and function. Our goal is to ensure the medication supports long-term well-being, particularly for people who may be at higher risk of muscle loss. This study involves (3) in-person study visits. At each visit, participants will be asked to: * Undergo magnetic resonance imaging (MRI) while resting and during exercise to take pictures of their heart, abdomen, and legs. * Complete tests to assess balance, sit-to-stand, walking speed, and handgrip strength. * Complete questionnaires related to demographics, health information, physical activity, and nutrition. * Have a blood sample collected from a vein in your arm. * Have your blood levels assessed through three finger pricks. * Complete three days of food records.

Inclusion Criteria: * Adults 18-80 years of age * Starting semaglutide for type 2 diabetes or weight loss * Able to safely undergo an MRI scan (including meeting the physical requirements for MRI equipment) Exclusion Criteria: * Current use of semaglutide for more than 2 weeks * Major recent heart issues or other severe health conditions * Concerns related to MRI use (including magnetic implants, pacemaker, severe claustrophobia) * Dependence on a mobility aid (unable to participate in exercise MRI)