A Balanced Fitness Regimen May Yield the Best Longevity Results
This suggests that current exercise guidelines — which suggest people do muscle-building workouts twice weekly and choose between either 150 minutes of moderate aerobic exercise or 75 minutes of vigorous aerobic exercise — might need to change to stress the need for all three types of workouts, Dr. López-Bueno says.

For example, instead of choosing between moderate and vigorous aerobic exercises, people might aim for 75 minutes of each in addition to two muscle-strengthening workouts a week, López-Bueno says. But more research is needed to determine what types of muscle-boosting workouts are best or how long people need to do these exercises — questions this study wasn’t designed to answer, López-Bueno adds.

The vast majority of study participants didn’t get the minimum recommended amount of exercise in the current guidelines. Only 6.6 percent of the participants in the study completed at least two muscle-strengthening workouts each week in addition to getting at least 150 minutes of moderate exercise or at least 75 minutes of vigorous exercise.

In fact, 72 percent of participants got less than 150 minutes of moderate aerobic exercise, less than 75 minutes of vigorous aerobic exercise, and fewer than two muscle-strengthening workouts each week.

Any Physical Activity Is Better Than None
Even for all these people who don’t get the minimum recommended amount of weekly exercise, it’s still possible to benefit from whatever amount of physical activity they can do, says Jessica Gorzelitz, PhD, a physical activity researcher in the department of health and human physiology at the University of Iowa in Iowa City, who wasn’t involved in the new study.

“It is important to consider one’s own starting point as a reference value for where to set goals,” Dr. Gorzelitz says. “For example, if a person reports no leisure time activity [no moderate, vigorous, or strength activity], truly they will benefit from any activity addition — so it’s okay to start small and work towards the guidelines.”

The study findings also suggest that after a certain point, the added benefits of even more aerobic exercise are minimal, says Keith Diaz, PhD, an exercise physiologist and an associate professor of behavioral at Columbia University Irving Medical Center in New York City, who wasn’t involved in the new study.

The best exercise is one that you can maintain and do for life, Dr. Diaz says. “If you’re short on time, vigorous exercise is the most time-efficient,” Diaz adds. “Ten minutes of vigorous exercise is equivalent to 20 minutes of moderate exercise.”

How to Tell if You’re Exercising Effectively
To get the greatest benefit, choose a workout you enjoy, and push yourself as hard as you can, says Adam Skolnick, MD, an associate professor at the NYU Grossman School of in New York City, who wasn’t involved in the new study.

“If you find that you can sing a song while exercising, you probably need to increase the intensity,” Dr. Skolnick says. “On the other hand, if you cannot speak at all while exercising, it may be too intense.”