Abstract Lack of consensus on the type and amount of exercise to safely increase bone mineral density (BMD) prevents many clinicians from providing detailed recommendations on how to increase physical activity. We present a young man with low bone density, who was initiated on a non-pharmacologic regimen of physician-directed high intensity resistance exercise (HIRE) and adequate nutrition support. A 28-year-old male was found to have a low bone density attributed to autoimmune hepatitis, chronic systemic glucocorticoids used for 7 years and poor lifestyle habits. Despite stopping steroids since 2014, his BMD was worsening in the femoral neck (FN) to 0.723 g/cm2 (Z-score -2.7) in 2018, representing a 3% loss from the prior year. His BMD in the total hip (TH) site also decreased from 0.775 g/cm2 (Z-score -2.1) to 0.751 g/cm2 (Z-score -2.3) in the same 1-year period (3.1% loss). The patient had no personal or family history of fractures, smoking or alcohol use, but did have a sedentary lifestyle and ate highly processed foods with poor nutritional value. After unremarkable evaluation for further causes of ongoing bone loss, in 09/2018 we initiated a tailored progressive high intensity resistance exercise (HIRE) program. Major compound movements such as squats, deadlifts, military press, and dynamic impact exercises such as medicine ball throws, jumps and farmers carry were performed 3 times a week, maintaining an intensity of >80% 1-repetition maximum with 5 repetitions. The HIRE program was modified every 3 months at endocrinology clinics. After the first year, one on one training with expert kinesiologist was introduced to correct exercise form. Nutrition recommendations were simple, focused on increasing weight, adequate dairy intake, and protein intake at 1.6g/kg of body mass. He maintained adherence to exercise and diet throughout 2018-2021. BMD measured by the same Lunar iDXA increased by 10.8% at the FN from 09/2018 to 09/2019. As often occurs in clinical practice, the patient had bone density scans performed at various centers throughout his years of care. Using BMD standardization algorithms, we estimate that after initiation of our HIRE and nutrition intervention, BMD increased at all sites (LS +9.7%, FN +17.7%, TH +12.7%) when compared to pre-intervention values. His most recent DXA scan on 12/2020 (Hologic Discovery) revealed a Z-score of -1.7 (LS), -1.5 (FN) and -1.5 (TH). We conclude that our HIRE and nutrition intervention lead to clinically significant bone density increases which are expected to lead to a reduction in fracture risk. Additionally, improved lifestyle habits and nutrition are expected to have multiple benefits beyond bone health. It is important that clinicians learn about different types of exercise programs to properly guide patients which could benefit. A HIRE program should be considered in select, able bodied patients with low bone density. Presentation: Saturday, June 11, 2022 1:00 p.m. - 3:00 p.m.