The purpose of this study is to examine whether muscle strength and balance will improve in women with frailty selected for dehydroepiandrosterone sulfate (DHEAS) levels below 550 ng/dl treated with DHEAS supplementation and Hatha yoga. Investigators believe the effects of both treatments will improve outcomes more than either treatment alone and may be additive; in addition, lean body mass, skeletal muscle mass, markers of bone turnover and physical performance will improve following treatment with DHEA and/or yoga.

Dehydroepiandrosterone (DHEAS) and yoga may mitigate or reverse the effects of aging and frailty on bone, muscle and balance loss. The mechanism of the effects may be direct - working through androgen or estrogen receptors in bone, muscle or brain. Or the effects may be indirect, countering effects of the stress response.

The specific aims of this study are:

1. To determine the effects of dehydroepiandrosterone sulfate (DHEAS) supplementation and/or Hatha yoga on muscle strength, balance, body composition and physical performance measures over 6 months in women with osteopenia and some degree of frailty
2. To determine the effect of dehydroepiandrosterone sulfate (DHEAS) supplementation and/or Hatha yoga on function (physical and cognitive), bone metabolism, and cardiovascular risk factors.

Inclusion Criteria:

• Women over age 65 years
• Bone mineral density t-score less than -1
• At least one of the five components of the frailty phenotype (low hand grip strength, low walking speed, low physical activity, weight loss or sense of exhaustion)
• DHEAS levels less than 550 ng/dl
• Able to come or be brought to the University of Connecticut Health Center (UCHC) for outpatient visits
• Mammogram within the preceding 12 months

Exclusion Criteria:

• Disease or medication known to affect bone or muscle metabolism (i.e., Paget's disease, osteomalacia or 25OHD level less than 10 ng/dl, hyperparathyroidism: current use of corticosteroids, calcitonin, heparin, phenytoin, phenobarbital, methotrexate, bisphosphonates, calcitonin, selective estrogen receptor modulator or PTH)
• Use of androgen or estrogen in the preceding year
• Use of psychiatric medications including antipsychotic medications and SSRI
• Metastatic or advanced cancer (other than skin cancer)
• History of breast cancer
• Active cardiac ischemia by history of angina or myocardial infarction in the preceding 6 months