The distinction between "replicates" and "repeated measures".

Replicates and repeated measures are very different. Consider a study where you compare three conditions, rest, during exercise and after exercise. 

If you do a study where the same person is measured in all three conditions you have repeated measures.  Each subject is measured at rest, then at exercise, then after exercise.

If you do a study with three groups of people, you collect replicates. If n=3, then you assess three people at rest, three different people during exercise, and three others after exercise. WIth n=3, the replicates of each group are called triplicates.