When people 65 and older did strength training twice a week, they lowered their odds of dying from any cause by almost half during a 15-year study.
Lower mortality risk
"The secret to a longer and healthier life may not be available in pill form, but it may look like a barbell," said lead study author Dr Jennifer Kraschnewski. She's an assistant professor of medicine and public health sciences at Penn State College of Medicine, in Hershey, Pennsylvania.
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"Strength training can substantially decrease mortality risk, and more importantly, some of our other work demonstrates the impact of strength training on improving functional limitations [in older people]," she added.
The study included data on more than 30,000 adults, all 65 and older. Information was collected from 1997 through 2001 through the U.S. National Health Interview Survey.
Nearly 10 percent of the adults in the study reported strength training at least twice a week. That's consistent with guidelines from the American College of Sports Medicine/American Heart Association (ACSM/AHA).
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Kraschnewski said this training included muscle-strengthening activities for the legs, hips, back, abdomen, chest, shoulders and arms.
While the study didn't prove cause-and-effect, it found that people who did strength training at least two days a week were 46 percent less likely to die from any cause.
Benefit of longevity
And they were 41 percent less likely to die from heart disease, Kraschnewski said. She added that seniors who did at least two days of strength training were also 19 percent less likely to die from cancer compared to those who didn't do the training.
Responding to the study findings, orthopaedic surgeon Dr Brad Thomas said, "Strength training has been well identified as a means to strengthen our bones and joints, but with this study we have a new benefit of longevity." Thomas, who was not involved with the study, is an associate professor at UCLA David Geffen School of Medicine.
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Previous studies have shown that strength training may improve muscle mass and chronic conditions such as diabetes, osteoporosis, lower back pain and obesity.
Stronger muscles may also result in better stamina, physical function, and balance, according to background information in the study.
ACSM/AHA guidelines also recommend that adults participate in moderate-intensity (such as brisk walking) aerobic activity for 150 minutes each week. That's 30 minutes a day, five days a week.
If you are performing vigorous-intensity aerobic activity (such as jogging or running), the guidelines suggest 75 minutes each week.
Kraschnewski urged older adults who have not been active to talk with a doctor before starting an exercise programme.
"In general, there are safe exercises for everyone, but it may require tailoring for your specific conditions," she said. "Strength training can be done at home and many exercises don't actually require equipment."
A few of her suggestions include doing pushups, abdominal crunches and leg squats, all of which use one's own body weight.
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Kraschnewski said resistance bands are another great option for home-based programmes. These inexpensive bands or tubes provide resistance when stretched and can be used for strength training exercises in all major muscle groups, she said.
If you feel that you could benefit from additional help, consider joining a gym that offers coaches to help create an exercise regimen, she suggested.
"Typically, two to three exercise sessions a week for 20 to 30 minutes are enough for most people to develop results," said Kraschnewski. "Our studies have demonstrated older adults can double their strength in just 12 weeks."
Both Kraschnewski and Thomas said there's no age cutoff when it comes to getting benefits from aerobic exercise and strength training.
"Older adults have the ability to achieve strength similar to those decades younger by engaging in simple strength training routines," Kraschnewski said.
The study findings were published recently in the journal Preventive Medicine.
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