GLP-1R Actions on Muscle and the Skeleton

Inclusion Criteria: * Subjects will have a BMI between 30kg/m2 * 40kg/m2 (inclusive) * Be between 18 and 50 years of age (inclusive). * Non-Hispanic Black males and females will be enrolled at PBRC. * Rural males and females will be enrolled at MaineHealth. * Female subjects will be premenopausal. * Females have had their last menstrual period less than 60 days before screening. * Females have the absence of menopausal-associated vasomotor symptoms. * All subjects must be able to use Lifestyle Toolkit as prescribed for intervention arm. Exclusion Criteria: \- Males and females over the age of 50 years of age * Menopausal females. * Subjects on systemic corticosteroids or other agents known to increase loss of muscle and bone mass. * Subjects who are on medications that increase or decrease weight status. * Subjects having contraindications to tirzepatide in the package insert. * Subjects with a history of malignancy other than non-melanoma skin cancer * Subjects with known osteoporosis or are on osteoporosis therapies (gonadal hormones or hormone antagonists). * Subjects with uncontrolled thyroid or parathyroid disease that may influence the study results. * Subjects with a clinically significant hematologic abnormality, kidney disease, liver disease, or diabetes. * Females of childbearing potential who do not agree to using an effective method of contraception during the study. Medically acceptable methods include oral contraceptive medication, an intrauterine device (IUD), an implantable contraceptive (such as Implanon), or a barrier method (such as condom or diaphragm with spermicide). Injectable contraceptives such as Depo-Provera are a cause for exclusion in that they can cause bone loss. Abstinence is acceptable, as is sexual activity exclusively with same sex partners. Fertility Appreciation Based Methods (natural family planning) are also acceptable forms of addressing childbearing potential in all subjects. A urine pregnancy test (UPT) will be performed on all females of childbearing potential at the screening visit, 3 and 6 months. * Unable to follow Lifestyle Toolkit as prescribed for intervention arm. * Patient Health Questionnaire-9 (PHQ-9) Score equal to or greater than 15 (clinical depression). * Adults who are unable to consent. * Individuals who are not yet adults (infants, children and teenagers). * Pregnant females. * Incarcerated individuals. * Contraindication to MRI - including but not limited to non-removable metallic or electronic implants, claustrophobia or other fear of confinement, inability to tolerate loud scanner noise, body weight greater than 500 pounds. * Subjects with a baseline level of 25-OH vitamin D \<15 ng/ml will be excluded from the trial. The subject's physician will be notified, and the subject will be referred to their primary care physician. * Any significant EKG abnormalities that are considered a risk for utilizing weight management therapies.