Editor's note: This popular story from the Daily Briefing's archives was republished on June 23, 2023.

Writing for the New York Times, Rachel Fairbank explains how physical activity helps individuals live a longer, healthier life, and outlines a growing body of evidence that suggests both cardio and strength training are important for longevity. 

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'A mix of both aerobic and strength training' provides the most benefit

In a new study published in the British Journal of Sports Medicine, researchers found that an exercise routine of either aerobic exercise or strength training was associated with a lower risk of dying. Further, they found that a routine that included one to three hours a week of aerobic exercise and one to two strength training sessions a week was associated with an even lower mortality risk.

For the study, researchers used National Health Interview Survey data, which tracked 416,420 adults between 1997 and 2014. For the survey, participants completed questionnaires that asked about the types of physical activity they engaged in, including their level of moderate or vigorous exercise, and the number of muscle-strengthening exercise sessions they completed in a week.

After the researchers adjusted for age, gender, income, education, marital status, and chronic conditions, they found that people who engaged in one hour of moderate to vigorous aerobic exercise each week had a 15% lower mortality risk. In addition, they found that mortality risk was 27% lower for participants who reported engaging in moderate to vigorous aerobic exercise three hours a week.

Participants who also completed one to two strength-training sessions each week had an even lower mortality risk: 40% lower than participants who did not exercise—a difference that is equivalent to a nonsmoker and a person who smokes a half a pack of cigarettes each day.

Marking the switch from a sedentary lifestyle to an active exercise regimen is comparable to "smoking versus not smoking," according to Carver Coleman, a data scientist and one of the study's authors.

Notably, this study joins a growing body of evidence that shows the importance of strength training in longevity and overall health, Fairbank writes.

"The study is exciting because it does support having a mix of both aerobic and strength training," said Kenneth Koncilja, a gerontologist at the Cleveland Clinic, who was not involved in the study. "That is definitely something I talk with my patients about all the time."

The link between longevity and strength training

Many experts have noted it can be challenging to study the relationship between longevity and strength training since so few people regularly incorporate it into their exercise regimen.

For instance, in the new study, only 24% of participants said they regularly completed strength training sessions, while 63% said they did aerobic workouts. "Even with huge cohorts like we had here, the numbers are still relatively small," said Arden Pope, an economist at Brigham Young University and one of the study's authors.

However, in a meta-analysis published in February in the British Journal of Sports Medicine, researchers were able to assess the impact strength training had on longevity.

The researchers found that the biggest reduction in risk was associated with 30 to 60 minutes of strength training each week, which resulted in a 10% to 20% decline in the risk of mortality, cardiovascular disease, and cancer.

According to Haruki Momma, a sports scientist at Tohoku University and one of the study's authors, additional research is needed to determine the optimal amount of strength training required to reduce risk.

"Even though more research is needed, experts generally agree that regular strength training can have important benefits for healthy aging, including maintaining a high quality of life," Fairbank writes.

"You will function at a much higher level, for longer, if you have good muscle strength," said Bruce Moseley, an orthopedic surgeon at Baylor College of Medicine.

While "we progressively lose muscle mass as we age," Monica Ciolino, a physical therapist at Washington University in St. Louis, noted that "we can absolutely fend off the negative effects" with regular strength training.

To create an effective strength training regimen, Moseley suggests maintaining a consistent schedule and taking steps to avoid overuse injuries. "Keep it at a light and easy level at first," he said. "Once your body starts getting adjusted, then you can start increasing."

According to Moseley, the most important thing is making it a habit. "Not only can this help you live longer, it will improve your quality of life," Fairbank writes.

"When I ask people, 'What does successful aging mean to you?' people say they want to be independent, they want to maintain their function and quality of life, they want to do the things that they want to do," Koncilja said. "It's not necessarily just living as long as possible." (Fairbank, New York Times, 8/29)