A new study suggests that going beyond current guidance on moderate and vigorous physical activity levels may add years to one’s life.
Americans are advised to do a minimum of 150-300 minutes a week of moderate exercise or 75-150 minutes a week of vigorous exercise, or an equivalent combination of both, according to U.S. Department of Health and Human Services Physical Activity Guidelines.
Results from more than 100,000 U.S. adults followed for 30 years showed that.
Adults who reported completing four times the minimum recommended activity levels saw no clear incremental mortality benefit but also no harm, according to the study, published in the journal Circulation.
“I think we’re worried more about the lower end and people that are not even doing the minimum, but this should be reassuring to people who like to do a lot of exercise,” senior author Edward Giovannucci, MD, ScD, with the Harvard T.H. Chan School of Public Health, Boston, told this news organization.
Some studies have suggested that long-term, high-intensity exercise (e.g., marathons, triathlons, and long-distance cycling) may be associated with increased risks of atrial fibrillation, coronary artery calcification, and sudden cardiac death.
A recent analysis from the Copenhagen City Heart Study showed a U-shaped association between long-term all-cause mortality and 0 to 2.5 hours and more than 10 hours of weekly, leisure-time sports activities.
Most studies suggesting harm, however, have used only one measurement of physical activity capturing a mix of people who chronically exercise at high levels and those who do it sporadically, which possibly can be harmful, Dr. Giovannucci said. “We were better able to look at consistent long-term activity and saw there was no harm.”
The study included 116,221 participants in the Nurses’ Health Study and the Health Professionals Follow-up Study between 1988 and 2018, who completed up to 15 (median, 11) questionnaires on their health and leisure-time physical activity that were updated every 2 years.
Most were White (96%), 63% were female, and the average age and body mass index over follow-up was 66 years and 26 kg/m2. During 30 years of follow-up, there were 47,596 deaths.
‘Any effort is worthwhile’
The analysis found that individuals who met the guideline for long-term vigorous physical activity (75-150 min/week) cut their adjusted risk of death from cardiovascular disease (CVD) by a whopping 31%, from non-CVD causes by 15%, and all-causes by 19%, compared with those with no long-term vigorous activity.
Those completing two to four times the recommended minimum (150-299 min/week) had a 27%-33% lower risk of CVD mortality, 19% lower risk of non-CVD mortality, and 21%-23% lower risk of all-cause mortality.
Higher levels did not appear to further lower mortality risk. For example, 300-374 min/week of vigorous physical activity was associated with a 32% lower risk of CVD death, 18% lower risk of non-CVD death, and 22% lower risk of dying from any cause.
The analysis also found that individuals who met the guidelines for moderate physical activity had lower CVD, non-CVD, and all-cause mortality risks whether they were active 150-244 min/week (22%, 19%, and 20%, respectively) or 225-299 min/week (21%, 25%, and 20%, respectively), compared with those with almost no long-term moderate activity.
Those fitting in two to four times the recommended minimum (300-599 min/week) had a 28%-38% lower risk of CVD mortality, 25%-27% lower risk of non-CVD mortality, and 26%-31% lower risk of all-cause mortality.
The mortality benefit appeared to plateau, with 600 min/week of moderate physical activity showing associations similar to 300-599 min/week.
“The sweet spot seems to be two to four times the recommended levels but for people who are sedentary, I think one of the key messages that I give my patients is that any effort is worthwhile; that any physical activity, even less than the recommended, has some mortality reduction,” Erin Michos, MD, MHS, associate director of preventive cardiology at Johns Hopkins University, Baltimore, said in an interview.
Indeed, individuals who reported doing just 20-74 minutes of moderate exercise per week had a 19% lower risk of dying from any cause and a 13% lower risk of dying from CVD compared with those doing less.
Current American Heart Association (AHA) recommendations are for at least 150 minutes per week of moderate-intensity aerobic exercise or 75 minutes per week of vigorous aerobic exercise, or a combination of both.
“This suggests that even more is probably better, in the range of two to four times that, so maybe we should move our targets a little bit higher, which is kind of what the Department of Health and Human Services has already done,” said Dr. Michos, who was not involved in the study.
Former AHA president Donna K. Arnett, PhD, who was not involved in the study, said in a statement that “we’ve known for a long time that moderate or intense levels of physical exercise can reduce a person’s risk of both atherosclerotic cardiovascular disease and mortality.
“We have also seen that getting more than 300 minutes of moderate-intensity aerobic physical activity or more than 150 minutes of vigorous-intensity aerobic physical exercise each week may reduce a person’s risk of atherosclerotic cardiovascular disease even further, so it makes sense that getting those extra minutes of exercise may also decrease mortality,” she added.