We LIVE for stories of perseverance, grittiness, and determination. We hear them all the time from racers in our community, but we also love to report on inspirational, badass stories and studies from OUTSIDE the Spartan Universe — stories and studies that we can learn from, that can help us become even more unbreakable. In Tough News, we share what we're hearing, why it's important, and why Spartans need to pay attention.

A new study published in the American Heart Association's flagship journal, Circulation, confirms what Spartans have been saying (and practicing) for a decade: The more you exercise each day, the less likely you are to die. But with tight schedules, work deadlines, and family obligations, just how much should you be training each day? And how many weekly minutes does it take to maximize your body's defense against all-cause mortality? Here's what you need to know.

How Long Should American Adults Exercise Each Day?

The United States Department of Health and Human Services' (HHS) 2018 Physical Activity Guidelines for Americans — after finding that 80% of U.S. adults and teens don't get enough daily physical activity — outlined minimum activity recommendations for Americans. Adults should accumulate 150 to 300 minutes of moderate-intensity aerobic physical activity and/or 75 to 150 minutes of vigorous-intensity aerobic physical activity per week. The guidelines also recommend two or more days of strength training for those 18 years or older.

But is that really enough? And if you exercise even more, how much of a difference will it make to your overall health? Is it marginal or sizable?

How Many Minutes of Exercise Does It Take to Maximally Reduce Your Risk of Death?

The Circulation study, published in July 2022, began collecting data from 121,701 female nurses (ages 30-55) in 1976, and continued further in 1986 with 51,529 male health professionals (ages 40-76). At enrollment — and every two years thereafter for 30 years — the participants self-reported answers to questionnaires on lifestyle, leisure-time activity, and medical reports.

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After 30 years, the study identified 47,596 deaths out of its 116,221 total participants. Those who met the HHS-recommended guidelines for moderate-intensity activity (like walking or lifting weights) were 22-25% less likely to die from cardiovascular-related diseases (and 20-21% less likely to die from any cause). Plus, those who exercised vigorously (ran, swam, or biked) within the guidelines had a 31% lower risk of experiencing a cardiovascular-related death, and a 19% lower risk of all-cause death.

This is great news for those who are already moderately active throughout the week, but even better news for Spartans, who tend to train heavily on most days, with just a few days of rest weekly. The study further concluded that a 21-23% lower mortality rate could be achieved by accumulating two to four times the recommended amount of vigorous activity, and a reduced risk rate of up to 26-31% could be seen for those engaging in two to four times the proposed moderate-intensity activity.

Can You Exercise Too Much?

The greatest correlation to lower mortality appeared to come with 150 to 300 weekly minutes of long-term vigorous physical activity, and the study's findings continue to support the HHS recommendations' success. However, there also weren't any adverse cardiovascular effects reported by those who exercised more than four times the recommended vigorous amount.

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"Previous studies have found evidence that long-term, high-intensity, endurance exercise such as marathons, triathlons, and long-distance bicycle races may increase the risk of adverse cardiovascular events, including myocardial fibrosis, coronary artery calcification, atrial fibrillation, and sudden cardiac death," the American Heart Association said in a press release.

"This finding may reduce the concerns around the potential harmful effect of engaging in high levels of physical activity observed in several previous studies," Dong Hoon Lee, Sc.D., M.S., a study author and a Harvard T.H. Chan School of Public Health research associate, said in the AHA's release. 

So not only are you safe to continue pushing your body to its absolute limit with the endurance-based events that Spartans thrive off of, but you should keep training hard every week like your life depends on it ... because it actually does.