Incorporating Nutrition, Vests, Education, and Strength Training in Bone Health (INVEST in Bone Health)

The main goal of the proposed study is to compare the effects of weight loss (WL) alone with WL plus weighted vest use or WL plus resistance exercise training (RT) on indicators of bone health and subsequent fracture risk.

The study team proposes that a 12 month trial in 150 older (60-85 years) adults with obesity (Body mass index or BMI=30-40 kg/m2 OR 27.0-\<30 kg/m² and one obesity-related risk factor) randomized to one of three interventions (n=50/group): WL alone (WL; caloric restriction targeting 10% WL); WL plus weighted vest use (WL+Vest); targeting ≥8 hours/day, weight replacement titrated up to 10% WL); or, WL plus structured RT (WL+RT; 3 days/week). Total hip trabecular volumetric bone mineral density (vBMD) is the primary outcome. This outcome will be complemented by exploratory assessment of several fracture-related risk factors, including: (1) femoral neck and lumbar spine vBMD, cortical thickness, finite element modeling of bone strength, and regional fat and muscle volumes, measured by CT; (2) areal bone mineral density (aBMD) at the total hip, femoral neck, lumbar spine, and distal radius; trabecular bone score; and total body fat/lean masses, measured by dual energy x-ray absorptiometry (DXA); (3) muscle function and strength; (4) biomarkers of bone turnover; and (5) bone-regulating hormones/cytokines known to influence bone metabolism during WL. Therefore, the investigators Specific Aims are to:

Aim 1: Determine the effects of WL+Vest compared to WL and WL+RT on 12 month change in total hip trabecular vBMD. Despite similar reductions in total body weight, Hypothesis 1: Participants in the WL+Vest group will show attenuated losses of total hip trabecular vBMD versus WL; and Hypothesis 2: Loss in total hip trabecular vBMD will be no greater in WL+Vest compared to WL+RT.

Aim 2: Explore the effects of WL+Vest compared to WL and WL+RT on the 12 month change in fracture-related risk factors. Despite similar reductions in total body weight, we hypothesize that WL+Vest and WL+RT will demonstrate improvements in fracture-related risk factors compared to WL.

Eligibility Criteria:
Inclusion Criteria:

* Age 60-85 years
* BMI=30-40 kg/m\^2 or BMI 27.0-\<30.0 kg/m\^2 plus one risk factor
* Weight stability - no weight loss \> 5% in past 6 months
* No contraindications for safe and optimal participation in exercise training/vest use.
* Approved for participation by Study Coordinator
* Willing to provide informed consent; agree to all study procedures and assessments; Able to provide own transit to assessment/intervention visits
* Willing to complete online/electronic study forms and participate in virtual group sessions, as needed.

Exclusion Criteria:

* Weight greater than 450 lbs
* Dependent on cane or walker: \>2 falls (injurious on non-injurious) in past year
* Any contraindications for participation in voluntary weight loss
* Smoker (\>1 cigarette/d or 4/wk within yr); Excessive alcohol use (\>14 drinks/wk)
* Participation in regular resistance training and/or high intensity/high impact aerobic exercise for \>60 mins per day on \> 5 days/week for the past 6 months
* Evidence of cognitive impairment (MoCA\<20)
* Osteoporosis (self-report and on prescription medication, T-score \< or = -2.5 on total hip, femoral neck, lumbar spine or distal radius scan at screening visit, or fracture risk assessment tool (FRAX) 10-year risk scores \>3% for hip fracture or \>20% for major osteoporotic fracture (TBS adjusted FRAX is preferable if available)
* Self-reported prior spine, hip, wrist, or shoulder fracture after age 40 (except when caused by trauma or fall from height)
* Chronic back/shoulder/knee pain with current or past (within 1 year) prescription medication use for at least 3 months
* Severe, diagnosed arthritis (osteoarthritis, rheumatoid arthritis, or gout) with current or past (within 1 year) prescription medication use for at least 3 months
* Past (ever) or planned (next 12 months) back surgery
* Past (6 months prior) or planned (next 12 months) joint replacement surgery; or past (ever) unilateral or bilateral hip replacement surgery
* Past (ever) metal device or fixation in the hip, pelvis, or femur
* Uncontrolled hypertension (BP \> 160/90 mmHg)
* Current or recent past (within 1 year) severe symptomatic heart disease, uncontrolled angina, stroke, chronic respiratory disease requiring oxygen, neurological or hematological disease requiring treatment for at least 3 months in past year
* Cancer requiring treatment in past year, except non-melanoma skin cancer
* Low Vitamin D (\<20 ng/mL)
* Abnormal kidney or liver function (2x upper limits of normal)
* estimated glomerular filtration rate (eGFR)\<45 mL/min/1.73m2,
* Anemia (Hb \<13 g/dL in men/\<12 g/dL in women)
* Uncontrolled diabetes (fasting glucose \> 140 mg/dL)
* Regular use of: growth hormones, weight loss medications, oral steroids, insulin, or prescription osteoporosis medications in the past year
* No home computer, laptop or tablet with reliable home internet OR no smartphone (touch-screen enabled phone) with reliable unlimited mobile internet
* Involved in another behavioral/interventional research study, weight loss program, or undergoing physical therapy.
* Unable to tolerate diet, vest, or CT scan (claustrophobia)
* Judged unsuitable for the trial for any reason by clinic staff