You know that maintaining muscle strength is vital for staying healthy and agile. But not everyone has the time (or the desire) to slog through multiple sets of weight-lifting exercises.

Here’s another way: A new study has found that the same results normally achieved by doing multiple sets of several exercises can be achieved with just one set of these exercises—provided you do it the right way.

Read on to find out how.

WHAT EXERCISE GUIDELINES DON’T TELL YOU

Research up until now hadn’t pinned down the precise number of sets of weight-lifting exercises needed to build sufficient muscle. In a typical routine, you’d either lift weights or use a machine eight to 12 times, and then move on to another weight or machine, so that you strengthen the major muscles in your upper and lower torso and your core. That’s a set.

Trainers and coaches typically recommend at least two and often three or more sets of each type of exercise per workout—that’s because older studies found that doing multiple sets of resistance exercises maximized muscle strength. Problem: These studies measured muscle strength only immediately after one workout. But exercise guidelines should be based on what happens over weeks and months, not just in a single day.

To find out how much weight training is actually required to build muscle strength and size over time, exercise scientists at Lehman College in Bronx, New York, along with colleagues in New Zealand and Australia, recruited 34 healthy young men. The researchers measured muscle size, strength and endurance before the study and randomly divided participants into three groups…

  • One group did one set of weight-lifting reps three times a week on nonconsecutive days—three sets in total for the week.
  • Another group did three sets at each session—nine total sets per week.
  • The remaining group did five sets at each session—15 total sets per week.

Each set consisted of seven common weight-lifting moves for the upper and lower body, such as machine leg presses and lateral pulldowns. Each exerciser had to do each exercise “to failure,” an common practice to maximize effectiveness: The weight had to be heavy enough that a participant could just make it to the end of one set (eight to 12 reps) in good form. The men worked with trainers to adjust their individual sessions. (Those who did multiple sets rested for 90 seconds between sets.)

Participants ate their normal diets but were asked not to take any supplements, including those meant to improve muscle strength. Since protein is needed to build muscle, however, they were given a small protein supplement on training days—equivalent to the amount of protein in less than three ounces of chicken.

ONE SET EQUALS FIVE

After eight weeks, the men returned to the lab for follow-up muscle-size measurements via ultrasound and for muscle strength and endurance testing. All of them were stronger than they had been two months earlier.

Surprising finding: The gain in muscle strength from doing one set of reps in each workout was essentially the same as that  achieved by doing three or five sets. The gain in muscle endurance, the length of time you can perform a physically demanding task, was also equivalent.

Time savings: Doing just one set took the study subjects only 13 minutes versus 40 minutes for three sets and 68 minutes for five sets. If you do three workouts each week, as recommended by the study authors, what this study suggests is that you might get the same results in a total of 39 minutes per week compared with two hours (for three sets) or nearly three-and-a-half hours (for five sets).

There was one extra benefit to doing five sets—bigger muscles. Participants who did five sets in each workout had more muscle mass than those who had done either one or three sets. But strength and endurance testing showed that the five-set group wasn’t noticeably stronger—a key goal for health. So if want to make your muscles stronger to improve your health and improve your ability to do all the things you want during an active day—and bulking up isn’t your goal—one set of repetitions may be all you need.

The results don’t apply just to newbies. If you’re already doing resistance exercises, either on machines or with free weights or with traditional exercises like pushups, you can keep building strength with this one-set training prescription—provided you keep adjusting the weight so you are lifting to the point of exhausting your muscles by the end of the set. That is key to the whole discovery. And even though the study included only young men, the lead researcher believes the results should be similar for women and older people.

If you haven’t done any weight training or are concerned about the safety of lifting heavy weights, ask a strength and conditioning trainer at your local gym to devise an appropriate routine for you.

Note: If you have a medical condition, check with your doctor first… and if you have arthritis or osteoporosis, you may want to try lifting lighter weights instead. You’ll just need to increase the number of reps needed to get to exhaustion—the point where you can’t lift that particular weight any more. Your doctor can guide you.