Lifestyle Intervention for the Reduction of Breast Cancer Risk in Normal Weight Women

This trial studies how well a lifestyle intervention works in reducing breast cancer risk through changing body composition and decreasing inflammation in normal weight women. This trial may help researchers learn more about diet and exercise programs designed to decrease body fat in postmenopausal women who are of normal weight but have an elevated risk of breast cancer because of excess body fat.

Inclusion Criteria: * Age 50-69 years old * Postmenopausal woman (absence of menstruation for at least one year, or history of bilateral oophorectomy) * Self-reported height and weight indicating a BMI \>= 18.5 and \< 25 kg/m\^2 * No contraindications to exercise (either no positive responses on the Physical Activity Readiness Questionnaire, or clearance from a health care provider certifying that the participant is healthy enough to exercise) * No history of invasive cancer, other than non-melanoma skin cancer * No history of renal disease * Able to walk without an assistive device * Not within 3 months of major surgery * Able to speak/read/write in English * Has internet access on a computer or mobile device * A trunk fat mass \>= 9.4 kg as indicated by a dual x-ray absorptiometry (DXA) scan * Height and weight indicating a BMI of \>= 18.5 and \< 25 kg/m\^2 verified at the screening visit Exclusion Criteria: * MD Anderson employees that report to the principal investigator of this study * Participants that cannot engage in the exercise program for more than three weeks during the study period * Participants that are currently doing strength exercises that work all major muscle groups (defined as: participants who complete more than 16 repetitions per exercise in their current resistance training regimen, or who don't find their last 1-2 reps to be difficult in their current regimen, or who increase the weight in their current routine).