Immune Cells During Disuse and Recovery

Eligibility Criteria

• 1. Age between 18-35 and 60-85 yrs
• 2. Ability to sign informed consent
• 3. Free-living, prior to admission
• * History of cardiovascular disease (e.g., CHF, CAD, right-to-left shunt)
• * History of endocrine or metabolic disease such as hypo/hyperthyroidism and diabetes
• * History of kidney disease or failure
• * Vascular disease
• * Risk of DVT including family history of thrombophilia, DVT, pulmonary emboli, myeloproliferative diseases including polycythemia (Hb\>18 g/dL) or thrombocytosis (platelets\>400x103/mL), and connective tissue diseases (positive lupus anticoagulant), hyperhomocystinemia, deficiencies of factor V Leiden, proteins S and C, and antithrombine III
• * Use of anticoagulant therapy (e.g., Coumadin, heparin)
• * Elevated systolic pressure \>150 or a diastolic blood pressure \> 100
• * Implanted electronic devices (e.g., pacemakers, electronic infusion pumps, stimulators)
• * Cancer or history of successfully treated cancer (less than 1 year) other than basal cell carcinoma
• * Currently on a weight-loss diet
• * Chronic systemic corticosteroid use (≥ 2 weeks) within 4 weeks of enrollment and for study duration (intra-articular/topical/inhaled therapeutic or physiologic doses of corticosteroids are permitted)
• * Androgens or growth hormone within 6 months of enrollment and for study duration (topical physiologic androgen replacement is permitted)
• * History of stroke with motor disability
• * A recent history (\<12 months) of GI bleed
• * History of liver disease
• * History of respiratory disease (acute upper respiratory infection, history of chronic lung disease)
• * Pregnancy as determined by a pregnancy test
• * Any staff members who report directly to an investigator or who report to someone who reports directly to an investigator.
• * Any other condition or event considered exclusionary by the PI and faculty physician