Effects of Creatine and Resistance Exercise Training in People With HIV Infection

Inclusion Criteria: * Clinically stable, sedentary HIV-positive adults who are on optimized antiretroviral regimens and plan to remain so during the study. * Men and women on hormone replacement therapy and women using hormonal contraceptives must have been on stable regimens for the preceding 6 months and plan to continue on such treatment throughout the study period. Exclusion Criteria: * Serum creatinine \> 1.5 mg/dl or clinical evidence of renal disease or prior kidney transplant * Creatine kinase (CK) \> 1.5 times the upper limit of normal (ULN) * Hemoglobin \< 8.5 g/dl * AST, ALT, or LDH \> 5 X ULN * Uncontrolled diarrhea (\> 6 stools per day) * Impaired oral intake * Persistent nausea or vomiting * Untreated hypogonadism * Pharmacologic use of growth hormone, testosterone, oxandrolone, nandrolone decanoate, oxymetholone, or other oral, injectable, or transdermal anabolic steroids, androstenedione, or dehydroepiandrosterone (DHEA) within the preceding 6 months (subjects with documented hypogonadism on stable testosterone replacement, defined as a dose \< 300 mg q2 weeks for the preceding 6 months, will be allowed to enroll) * Use of glucocorticoids, megestrol acetate, creatine monohydrate, cytokine inhibitors (thalidomide, pentoxifylline, ketotifen), drugs known to adversely affect renal function, cytokines, parenteral or tube feeding, or initiation of treatment for a systemic infection within 30 days prior to enrollment * History of angina, coronary heart disease, or congestive heart failure * Current pregnancy or lactation or plans to become pregnant. * Because vegetarians are known to have lower intramuscular concentrations of creatine and therefore may experience a much greater relative increase in muscle creatine levels, we will exclude such individuals from this study.