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Table 2 Study inclusion and exclusion criteria

From: Metformin to Augment Strength Training Effective Response in Seniors (MASTERS): study protocol for a randomized controlled trial

Inclusion criteria
• ≥65 years of age
• Independently mobile with an SPPB score 4–12
• Access to transportation
• Capable of providing informed consent (cognitively intact)
• Negative diagnostic (12-lead ECG), submaximal Graded Exercise Testing (GXT) (if applicable)
Exclusion criteria
• Obesity (body mass index (BMI) >30)
• Serum creatinine >1.4 because of risk of lactic acidosis with metformin
• History of structured, regular resistance exercise training within the past year (more than two times per week consistently)
• Chronic aspirin or non-steroidal anti-inflammatory drug (NSAID) use (unless it can be safely stopped prior to the biopsies) and any other use of an anticoagulant (e.g., Coumadin) or history of bleeding
• History of alcoholism or liver disease
• History of hypo- or hypercoagulation disorders including subjects taking Coumadin
• Any end-stage disease and/or a life expectancy less than 1 year
• Neurological, musculoskeletal, or other disorder that would preclude them from completing resistance training and all performance tests
• Uncontrolled hypertension, unstable or exercise-induced angina pectoris or myocardial ischemia, or congestive heart failure
• Diabetes mellitus: HgbA1C >6.5, or fasting glucose >126 mg/dl, or 2-h glucose (on oral glucose tolerance test (OGTT)) >200)
• Any other medical condition that would interfere with testing or increase one's risk of complications during exercise, as judged by the study physicians
• Any other condition or events considered exclusionary by the Principal Investigator and/or physician, such as non-compliance
• Lidocaine allergy (1% lidocaine is the local anesthetic used during the muscle biopsy procedure)
• Currently receiving androgen or anabolic therapy