Kava Aging and Mobility Study

Inclusion Criteria: * Age \> 70 years * 8 ≤ Insomnia severity index (ISI) ≤21 * 4m walking speed \<1 m/sec and \>0.44 m/sec * Mild to moderate physical impairment (Short Physical Performance Battery score \< 10) * Sedentary lifestyle (\< 150 min per week of moderate intensity physical activity) verified by CHAMPS questionnaire * Willingness and ability to give informed consent * Willingness to be randomized to the intervention groups * Availability for participation through duration of study Exclusion Criteria (General) * Failure to provide informed consent * History or clinical manifestation of diabetes, cholelithiasis, liver or renal disease, cancer, or progressive, degenerative neurologic disease (e.g., Parkinson's Disease, multiple sclerosis, ALS) * Abnormal laboratory markers (e.g., renal or liver abnormalities, elevated potassium levels, or hemoglobin and hematocrit below the lower limit of normal) * Residence in a Skilled Nursing Facility (SNF); residence in an Assisted Living Facility (ALF) or independent housing is allowed * Self-reported inability to walk one block * Significant cognitive impairment, defined as a known diagnosis of dementia or a Mini-Mental Status Exam score \< 24 * Severe rheumatologic or orthopedic diseases (e.g., awaiting joint replacement, active inflammatory disease) * Terminal illness with life expectancy less than 12 months, as determined by a physician * Severe cardiac disease, including NYHA Class III or IV congestive heart failure, clinic…