New Method Using Deuterium Labelled Creatine to Measure Total Body Skeletal Muscle Mass

One dose of D3 Creatine (60mg capsule) given orally on Day 1

Participants will consume an individual dosed level of creatine, based on their estimated muscle mass in doses of 0.03, 0.035, 0.04, 0.045 g.kg.Lean mass/day, increasing on a weekly basis. Final dose of 0.05 g.kg.Lean mass/day is then maintained throughout the study.