If you've ever been to outpatient physical therapy, worked with a personal trainer, or read articles on strength training, then you've probably been told to do 3 sets of 10 repetitions of an exercise. That assortment of sets and reps is everywhere. Why is that? This goes back to some of the same roots as the profession of physical therapy itself, World War II. You can learn a little more about the history of PT here.
In 1945, army physician, Thomas DeLorme, began experimenting with rehabilitation techniques for injured servicemen. He refined a type of strength training he called Progressive Resistance Exercise. The resistance was calculated off of the maximum amount of weight the person could move for 10 repetitions (their 10-repetition maximum, or 10RM). By 1948, the protocol looked like this:
- Set 1 – 10 repetitions at 50% their 10RM
- Set 2 – 10 repetitions at 75% their 10RM
- Set 3 – 10 repetitions at 100% their 10RM
He published his findings in 1951 and it was widely read by the medical community. It became a standard in rehabilitation. This protocol can be extremely effective, although it is also very challenging. A lot of what we do today was influenced by this work. Since DeLorme's time, we have continued to expand our knowledge of how to get the most out of various assortments of sets, reps, intensities, frequencies, and types of exercises. 3 sets of 10, however, sometimes just works so well. It's timely and easy to remember. When performed with adequate resistance, it's also highly effective.
