- According to a new study, a balanced regimen of moderate and vigorous activity, along with two muscle-strengthening sessions a week, can reduce the risk of various forms of mortality.
- The study also found even greater reductions in mortality risk by exceeding current physical activity guidelines.
- The study suggests that clinicians should ease their physically inactive patients into a healthy mix of exercises.
When it comes to lowering the risk of all-cause mortality or death from cardiovascular disease and cancer, is one form of exercise better than another? Or is there a particular combination of exercises that optimizes one’s chances of longevity?
A new study looks into the ideal combination of exercise types for living longer. It assesses various combinations of moderate aerobic physical activity (MPA), vigorous aerobic physical activity (VPA), and muscle-strengthening activity (MSA).
The study finds that a balanced amount of MPA, VPA, and MSA were most closely associated with a lower risk of dying, although the mix of activities depended on the type of mortality.
The optimal combination for lowering the risk of:
- all-cause mortality — was greater than 0–75 minutes each week of MPA together with over 150 minutes of VPA, plus two or more MSA sessions each week.
- cardiovascular disease (CVD) and cancer mortality — was more than 150–225 minutes of MPA, more than 0–75 minutes of VPA, plus two or more MSA sessions.
The 2020 World Health Organization exercise recommendations per week are 150 to 300 minutes of MPA, 75 to 150 minutes of VPA, or some relatively equivalent combination of them, plus MSA sessions on two days.
The study also found that MPA exercise levels greater than the current recommendations may reduce the risk of mortality even further.
With more than 300 minutes of MPA, greater than 0 to 75 minutes of VPA, and two or more MSA sessions per week, the researchers observed an approximately 50% lower mortality rate for all-cause and cancer mortality, along with a roughly three-fold lower mortality rate for CVD mortality.
The researchers analyzed data from the 1997 to 2018 U.S. National Health Interview Survey. It included 500 ,705 adults who were followed up for a median of 10 years (5.6 million person-years). Participants, ages 18–85, with a median age of 46.4, self-reported their exercise.
The study is published in
A seemingly paradoxical finding of the study is that two times the amount of VPA was associated with a reduction in all-cause mortality risk, but that twice the amount of MPA reduced the risk of cardiovascular and cancer mortality.
Professor Emmanuel Stamatakis, professor at the School of Health Sciences at the University of Sydney, and co-author of the study, suggested reasons why.
“MPA can be sustained for longer periods than VPA and MSA. It can be, therefore, a larger contributor to physical activity-related energy expenditure and weight maintenance or weight loss. [MSA] can contribute to the maintenance of muscle mass as we age,” said Prof. Stamatakis.
Maintaining muscle mass is beneficial for “dozens of chronic conditions,” he said. These include type 2 diabetes, cardiovascular disease, and avoiding falls that can result in fractures, loss of mobility, and loss of independence as people age.
“Such conditions and events are often treated as ‘age-related’ diseases, when in reality, they are the result of the population being chronically inactive with little muscle mass to support healthy metabolic function and sarcopenia,” said Prof. Stamatakis.
He noted at the same time that VPA and MSA offer benefits that MPA does not. VPA can improve cardiorespiratory fitness, for example.
The study’s corresponding author, Dr. Rubén López-Bueno, from the Department of Physical Medicine and Nursing at the University of Zaragoza, Spain, said of MSA that “
Prof. Stamatakis suggested a possible mechanism behind MSA’s effect on cancer risk: “Strength training can lower circulating levels of sex hormones, reducing the risks of breast and endometrial cancer in women, and prostate cancer in men.”
He added that for cancer patients with cachexia, strength training may help manage muscle dysfunction.
Dr. Melody Ding, associate professor at the Faculty of Medicine and Health at the Sydney School of Public Health, who was not involved in the study, was not so sure. “I won’t jump to the conclusion that MSA reduces cancer yet.”
“Although for some specific combinations, it seems to trend that way, the overall patterns of the combinations involving MSA and not involving MSA are still quite similar, and the confidence intervals tend to overlap,” she explained.
It is possible that MPA, VPA, and MSA also have a combined effect, though “The design of our study does not allow us to ascertain if there are synergistic effects among MPA, VPA, and MSA,” said Dr. López-Bueno.
“Whether these separated effects of each type of physical activity have a synergistic effect among them remains unknown and should be further investigated,” he said.
The key message of these findings, according to Dr. López-Bueno, “is that each type of physical activity matters in order to optimize mortality risk reductions.”
“No isolated type of physical activity or even the addition of two types of physical activity, even at higher levels, seems superior in terms of mortality risk reduction to the other three types combined,” he said.
“I think physicians should recommend participation in a range of activities, such as MPA, VPA, MSA, to the best of one’s capacity,” said Dr. Ding. “This is just one study.”
Dr. Ding also expressed concern that “we struggle to get people to meet the recommended levels, [so] raising the bar is likely to discourage people even more.”
While Prof. Stamatakis called for “holistic and thorough physical activity advice” for physicians, he cautioned that “clinicians should ideally tailor advice to baseline activity levels and ability levels.”
For physically inactive people, he said, “a wiser goal” would be to introduce moderate-intensity walking with just a few bursts of VPA and then later on build up to undertaking muscle-strengthening.