By David Schechter, MD

©2000

Some controversies never seem to go away. The fitness community has long debated whether there's an additional benefit to doing the second and third set while lifting weights. Some argue that the more sets or the more repetitions (reps) the better. Others contend that if you fatigue the muscle it will strengthen (and grow) and it doesn't matter when that happens-- first set or fifth.

A recent study, published in the American College of Sports Medicine's monthly publication "Medicine and Science in Sports and Exercise" (January 2000, p. 235-242; http://www.msse.org) looked at forty-two adults in their thirties and forties who were experienced at weight training. These individuals had been doing one set using a nine-exercise training circuit for at least a year. Half of this group continued to perform one set and half began to perform three sets of 8-12 reps to muscular failure three times a week for thirteen weeks using the same circuit.

At the end of the thirteen weeks, the researchers measured "one repetition" maximums and muscular endurance for chest press and leg extension exercises. They also measured body fat percentage.

The results showed that both groups significantly improved muscular endurance and strength. Both groups significantly improved lean body mass. No significant differences between groups were found.

What does this tell those of us who try to include strength training in our workouts? Not a whole lot.

First of all, both groups consisted of experienced exercisers. Secondly, the individuals had already demonstrated an ability to continue a nine-exercise circuit program three times a week for a year! This requires more discipline than I can muster and likewise for most of my patients. Thirdly, the fact that both groups improved is interesting because the only change in the control group was to exercise to muscle failure.

I believe that the ideal number of sets for most people who work out is two sets as a minimum and three if time allows. Most individuals are a bit inflexible and prone to injury. The first set can be a kind of warm-up, getting your muscles and ligaments ready for a harder set to follow. The second set can be done to muscle failure, or at least to fatigue, and that is usually sufficient. Some people prefer a third set, especially those who do higher reps, want to burn calories, or are looking for tone rather than strength and bulk.

The risk I see in the "one set" program is that in unsupervised individuals I would expect a higher rate of injury. I believe that individuals who are not prone to injury and have limited time could carefully use this approach.

Finally, we would all probably improve our strength, endurance and body composition if we were enrolled in a thirteen week study and knew we were going to be examined before and after. So while studies like this are academically interesting, practically speaking they don't change my opinion or practice much in this area.