Lifting Weights Linked With Living Longer

Can building our muscles help us live longer? According to new research, the answer is yes. Investigators found that regularly lifting weights was linked to a lower risk of death from any cause, with the exception of cancer. Their findings were published online on September 27 in the British Journal of Sports Medicine.

“Older adults who participated in weight lifting exercise had significantly lower mortality before and after factoring in aerobic exercise participation, and importantly, those who did both types of exercise had the lowest risk,” says lead author Jessica Gorzelitz, PhD, researcher in the division of cancer epidemiology and genetics at the National Cancer Institute, and assistant professor of health promotion at the University of Iowa in Iowa City. These findings provide strong support for the current Physical Activity Guidelines for U.S. adults, she adds.

Current Activity Guidelines Recommend Some Type of Strength Training

Current guidelines on physical activity for all adults recommend at least 150 weekly minutes of moderate intensity aerobic activity, or a minimum of 75 minutes of vigorous intensity aerobic activity, or an equal combination of the two — usually referred to as MVPA (moderate to vigorous physical activity). 

In addition to aerobic exercise, the guidelines recommend two or more days of strengthening activities that incorporate all major muscle groups, including the legs, hips, back, abdomen chest, shoulders, and arms.

Aerobic exercise, also known as “cardio,” is consistently associated with many health benefits, including a decreased risk of heart disease, better blood sugar control blood and lower risk of death. However, it’s still unclear if working out with weights might also help people live longer, according to the authors. 

Nearly 1 in 4 People Reported Lifting Weights Regularly

To evaluate the potential impact of exercising with weights — with or without regular aerobic exercise — researchers recruited participants from the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial, which began in 1993 and includes 154,897 men and women 55 to 74 years old from 10 different U.S. cancer centers.

A total of 99,713 people were included in the final analysis. Subjects were 53 percent female; 91.4 percent of the participants were white, 3.3 percent black, 1.4 percent Hispanic, and 3.9 percent were other races or did not identify their race.

The average age at the start of the monitoring period was 71 years old, and the average BMI (body mass index) was 27.8. A BMI of 18.5 to 24.9 is considered a healthy weight, and 25 to 29.9 is considered overweight, according to the Centers for Disease Control and Prevention (CDC). People with a BMI of 30 and above are considered to have obesity.

Participants were additionally asked if they had exercised with weights over the past year, and if so, how often. The answers collected ranged from less than once a month to several times a week.

The questionnaire also asked about the frequency and duration of both moderate and vigorous intensity physical activity over the past year. Moderate intensity was described as “activity where you worked up a light sweat or increased your breathing and heart rate to moderately high levels,” and vigorous activity as “activity strenuous enough to work up a sweat or increase your breathing and heart rate to very high levels.”

Researchers then placed the participants into 1 of 4 groups based on total weekly minutes of MVPA: 1. Inactive, 0 minutes; 2. Insufficient aerobic MVPA, 1 to 149 minutes; 3. Sufficient, 150 minutes to 300 minutes of moderate, or an equivalent amount of vigorous, activity; and 4. Highly active, 301 or more minutes of moderate, or an equivalent amount of vigorous activity.

Nearly 1 in 4 (23 percent) of people reported some weight lifting activity and 16 percent said they exercised with weights regularly between one and six times a week. Almost 1 in 3 people (32 percent) met the guidelines for physical activity, with 8 percent exceeding the guidelines (those exercising more than five hours a week) on MVPA.

Lowest Risk of Death in People Who Exercised and Lifted Weights

During the 9.5 year follow up, 28,477 of the participants died. Researchers found the following relationships between weight lifting, aerobic activity, and risk of death:

• Exercising with weights and aerobic MVPA were both independently associated with a lower risk of death from any cause, as well as from cardiovascular disease, but not from cancer.
• Overall, working out with weights without aerobic MVPA was associated with a 9 to 22 percent lower risk of death, depending on the amount: for example, using weights once or twice a week was associated with a 14 percent lower risk.
• In people who didn’t lift weights at all, aerobic MVPA was associated with a 24 to 34 percent lower risk of death from any cause, compared with those who reported neither MVPA nor exercising with weights.
• The lowest risk of death was seen among those who said they did both types of physical activity. For example, the risk of death was 41 to 47 percent lower in participants who reported meeting most recommended weekly levels of MVPA and also exercised with weights once or twice a week compared with participants who were physically inactive.

Researchers found similar results after controlling for several factors including education level, smoking, BMI, race and ethnicity, with one exception: sex. The associations between weight lifting, aerobic exercise, and early death were stronger in women.

These findings provide strong support for current recommendations to engage in both aerobic and muscle-strengthening activities, the authors wrote.

What Is It About Lifting Weights That Might Help People Live Longer?

Dr. Gorzelitz acknowledges that some people might wonder why weight lifting — even without aerobic exercise — could help people live longer.

“We know that muscle strengthening exercise is associated with a wide range of health benefits, which include increased strength and better physical function. We are still learning about the metabolic effects of weight lifting on bodily systems that may affect mortality risk, but we do know that this type of exercise can have a beneficial effect on body composition and other metabolic risk factors, such as blood pressure, inflammation markers and even blood cholesterol,” she says.

The amount of muscle (muscle mass) that a person has can affect metabolism, according to Cleveland Clinic. That’s because it takes more energy (calories) to build and maintain muscle compared with fat. People with more muscle mass often burn more calories.

Even a Small Amount of Strength Training May Have Benefits

These findings show that adding weight lifting to your physical activity routine, even for those who are aerobically active, is important for better health and longevity, says Gorzelitz.

If you’re intimidated by the idea of weight lifting and you’re unsure how to begin, Gorzelitz suggests baby steps. “Our results suggest that some is better than none, and it’s okay to get started slowly and progress as strength and confidence increases.”

Researchers Hope to Confirm Findings in a More Diverse Group of People

The authors acknowledged several limitations in the study. It was observational, which means that the findings don’t prove that weight lifting or physical activity actually caused people to live longer. It also relied on personal recall of strength training and exercise, and specific details on training intensity, training load, volume (sets and repetitions), and for how long participants had been exercising with weights weren’t available or included in the analysis.

The study focused only on weights, but the authors note that there are other ways to strengthen muscles, including body weight exercises such as push-ups and squats, Pilates, and plyometric exercises such as tuck jumps and burpees.

Future research should address more detailed assessments of weight lifting, beyond duration or frequency per week, says Gorzelitz. “My goal is to replicate these findings in more diverse populations to ensure results apply broadly, and this includes testing in clinical populations that may benefit, such as cancer survivors,” she says.

"As we advance our understanding, we can continue to refine our ability to implement safe, effective, and scalable interventions for both strengthening and aerobic exercises broadly so that all adults are able to achieve and maintain levels of activity recommended by the Physical Activity Guidelines," says Gorzelitz.