F.I.T.T.+Principle

F.I.T.T. Principlemedia type="custom" key="3818051"
Lindsey Palmer

http://www.teenhealthandwellness.com/article/313?search=F.I.T.T.%20Principle

http://www.healthgoods.com/Education/Fitness_Information/Fitness_Short_Course/fitt_principle.htm