Poison

"be sure NEVER TO REPEAT THE SELECTED EXERCISE(S) MORE THAN THE PRESCRIBED NUMBER OF TIMES since more harm will result than good by your unwittingly or intentionally disregarding this most important advice and direction. Why? Because this infraction creates muscular fatigue--poison. There is really no need for tired muscles."   Return to Life Through Contrology

This has to be one of the major faults of pilates mat presentation today. Aerobics instructors doing reps as endurance tests, building poison because they don't know any better.