This double-blind placebo controlled study will randomize adult survivors of childhood cancer who are 18 to 44 years of age, greater than ten years post first cancer diagnosis, and with low lean muscle mass to two groups: Resistance Training + Supplement (RT+S) or Resistance Training + Placebo (RT+P). Randomization will be stratified by sex and age (18-29 and 30-44 years) in a block size of 4. Three weekly resistance training sessions will occur over a 24 week period. The participants, investigator, trainer and individuals involved in testing will be blind to group assignment.