For years, Americans have been told by doctors and medical groups that 150 minutes per week of "moderate-intensity" exercise is the sweet spot to maximize health and longevity. That recommendation, which the Centers for Disease Control and Prevention promotes as ideal on their website and literature, equates to about 5 half-hour workouts per week. The reason that more exercise than that isn't often advertised is because, unlike some pursuits, the relationship between exercise and health benefits did not seem to scale linearly.
Now, a new, huge study casts doubt on that suggested number. Indeed, it turns out that getting twice as much exercise may actually bring with a host of health benefits. That suggests that millions of us who are moderately active, and following the exercise wisdom of our doctors, may want to consider doubling (or more) our weekly workout time in order to live longer and be healthier.
In the recent study — which was published in the scientific journal Circulation — scientists looked at a sample size of more than 116,000 US adults divided into two cohorts. The researchers analyzed self-reported leisure-time physical activity as the scientists followed up with members of the cohorts over a period of 30 years (1988 to 2018). Within that group, more than 47,000 passed away, while the rest supported a wide range of health conditions within that span.
As they discovered, a big factor in terms of determining how much you should exercise is the rigorousness of the exercise in question itself. As of 2018, the physical activity guidelines for Americans recommended a minimum of 150 to 300 minutes per week of moderate physical activity and 75 to 150 minutes per week of vigorous physical activity. If that already sounds strenuous, guess what? You should be doubling it — or, barring that, putting in "an equivalent combination of both."
Want more health and science stories in your inbox? Subscribe to Salon's weekly newsletter The Vulgar Scientist.
"The nearly maximum association with lower mortality was achieved by performing [approximately] 150 to 300 minutes per week of long-term leisure-time [vigorous physical activity], 300 to 600 [minutes] per week of long-term leisure-time [moderate physical activity], or an equivalent combination of both," the study's authors conclude.
The study is sufficiently thorough to be taken seriously, scientists say. One fitness expert, Harvard University professor of human evolutionary biology Daniel E. Lieberman, described the study to Salon in writing as "excellent" and added that "the results make total sense."
"[Fifty] minutes a week of moderate vigorous physical activity has been sort of set in stone as the standard minimum recommendation, but the word 'minimum' is often left out of the conversation, and few studies have ever argued that additional physical activity – especially vigorous physical activity — wasn't more beneficial," Lieberman explained. "The question has always been how much more and what intensity yields what degree of benefit. This study provides excellent evidence to bolster evidence that more than 150 minutes has benefits, especially when it is vigorous."
Referencing his own recent book "Exercised," Lieberman added that the study "also reinforces other evidence that concerns over exercising too much are overblown."
The news may be somewhat discouraging to people who have repeatedly tried to lose weight and found that it is difficult to shed the pounds. Scientific evidence overwhelmingly suggests that it is difficult for most people to both lose weight and keep it off, and that this difficulty can frustrate people who want to become healthier out of doing so. Yet even if the weight does not come off as quickly or significantly as you might like, your health will still benefit tremendously just by improving your diet and exercise habits.
"This study provides excellent evidence to bolster evidence that more than 150 minutes [per week] has benefits, especially when it is vigorous."
Lieberman made a similar point.
"What all these studies do show is that some exercise is always better than none, that eventually the benefits level off, and that mixing it up is also beneficial," Lieberman pointed out. "Moderate aerobic activity is the bedrock of every exercise regime, but some degree of strength training is important especially as we age, and some vigorous physical activity is almost always beneficial for those who can tolerate it safely." Moreover, the situation is complicated by "many factors such as age, gender, fitness, health status, previous physical activity history, and so on."
Yet one thing is indisputable: If you focus on being healthy, there are unlikely to be downsides.
"I'd remind readers that this study (like so many) looks only at lifespan, not healthspan," Lieberman explained. "Physical activity has stronger effects on healthspan than lifespan. Put differently, what physical activity really does is reduce one's vulnerability to a wide range of diseases, thus increasing healthspan, hence lifespan (as well as quality of life). I think we need to be more concerned about healthspan."
For more Salon articles about fitness: