HORMA: Hormonal Regulators of Muscle and Metabolism in Aging

Inclusion Criteria: * Men who are 65-90 years of age * Total serum IGF-1 (insulin-like growth factor) in the lower tertile for adults (56-167 ug/dl) * Total serum testosterone of 150-550 ng/dL Exclusion Criteria: * BMI (Body Mass Index) 35 kg/m2 or greater * Weight instability (\>3% change in prior 3 months) * Daily intake of total kilocalories less than or equal to 0.8X the RDA and intake of protein between 0.8 and 1.4 g/kg/day inclusive * Acute illness in the prior 30 days * Resistance training (wt lifting) in the past 12 months * Vigorous aerobic sports (Competing as a Master athlete in the prior 5 years; weekly swimming, racquet ball, cycling, tennis, in preceding 12 months) * Use of an anabolic agent (androgen, androgen precursor, rhGH, etc) in the preceding 12 months * Use of medications that might affect amino acid metabolism (e.g. beta-adrenergic blockers, beta-agonists, Ca2+ channel blockers, corticosteroids) * Fasting sugar greater than or equal to 126 mg/dl or diabetes requiring Rx * History of benign intracranial hypertension * Heart failure, active angina, or myocardial infarction in the prior 6 months or history of aortic stenosis * Uncontrolled hypothyroidism or hyperthyroidism * Rheumatoid arthritis, cirrhosis or active hepatitis * History of carpal tunnel syndrome * Prior cancer other than squamous or basal cell carcinoma of the skin * Sleep apnea or severe chronic lung disease * Anticoagulation with heparin or coumadin * Blood pressure not controlled with…