Joseph Pilates, a boxer, a gymnast, and a weight lifter, spent his life studying how humans and animals move. He knew that the purpose of exercise was not to strain or fatigue the body but rather preserve and energize it. Quality of movement is more significant than the quantity of reps and doing too many repetitions of an exercise and fatiguing muscles can end up in injury or just being plain exhausted. He believed it was much more efficient to do 3-8 repetitions really well, move on with your day, and go live your life.