Who needs more exercise: Women or men?

Exercising regularly is known to lower the risk of death, especially from heart problems. But scientists have discovered that that reduction in risk may differ between the sexes, with some people reaping greater benefits in less workout time.

So, who has to exercise more to reduce their risk of death: Women or men?

It turns out that women may reap these survival benefits more easily than men do. That's according to a large study published in 2024 in the Journal of the American College of Cardiology, which included data from more than 412,000 American adults ages 27 to 61, 55% of whom were female.

"The beauty of this study is learning that women can get more out of each minute of moderate to vigorous activity than men do," study co-lead author Dr. Martha Gulati, director of preventive cardiology in the Smidt Heart Institute at Cedars-Sinai, said in a statement. "It's an incentivizing notion that we hope women will take to heart."

The researchers collected participants' physical activity data via the National Health Interview Survey (NHIS), the largest and longest-running health survey in the U.S. The study looked at data collected between 1997 and 2017.

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The survey itself included questions about the types of exercises people performed and at what frequencies, durations and intensities. It also included participants' socioeconomic and demographic characteristics and medical conditions. The study excluded people who had certain health conditions at the start of the study time frame, such as coronary heart disease or cancer.

The researchers also looked through the National Death Index — a national database of death records — for deaths from any cause, as well as cardiovascular-related deaths. The data from survey participants is linked to this death-record data, so the researchers could then connect the data from their NHIS participants to the mortality data through the end of 2019. Overall, 39,935 participants died in the study timeframe, including 11,670 cardiovascular-related deaths, such as those from heart disease, heart attacks and strokes.

About 32% of the women and 43% of the men surveyed said they engaged in regular aerobic exercise, exercising for at least 150 minutes per week. Compared to inactive individuals of the same sex, women who exercised regularly had up to a 24% lower risk of death from any cause. For men who exercised regularly, however, the reduction in mortality risk reached only 15%.

Women also gained these survival benefits much more quickly than men did, the study found. In men, the highest reduction in death risk was seen at about 300 minutes of moderate-to-vigorous physical activity (MVPA) per week. That came with an 18% reduction in all-cause mortality. Women saw an equal benefit in less than half that time, at about 140 minutes of MVPA a week.

Women who trained more than that each week saw a greater benefit until they also peaked at around 300 minutes of weekly MVPA.

That trend held true across all durations of exercise, the researchers found, with women consistently seeing "proportionately greater benefits" for any amount of exercise than men did.

About 20% of women and 28% of men said they engaged in two or more sessions of strength training, such as lifting weights, each week. Overall, though, women reported an average of about 0.85 sessions per week, while men averaged 1.25 sessions per week.

On average, the women who strength-trained at least twice a week had a 19% lower mortality risk than women who trained less often or not at all. Men, on average, saw a 11% lower risk compared with inactive men.

These benefits were even greater when it came to cardiovascular health specifically.

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Compared with inactive individuals, women who performed aerobic physical activity had a 36% lower cardiovascular mortality risk, while for active men, this risk reduction was about 14%. Muscle strengthening produced similar outcomes, with a cardiovascular risk reduction of 30% for women and 11% for men, compared to baseline.

"What surprised us the most was the fact that women who do muscle strengthening had a reduction in their cardiovascular mortality by 30%," Gulati told NPR. "We don't have many things that reduce mortality in that way," she added.

The study did have some limitations, including that people's exercise data was self-reported, so it relied on the participants accurately reporting their activity levels.The study also tracked only leisure-time exercise, meaning it didn't count exercise completed during household tasks or as part of a job, which may have also contributed to the results. In addition, the study didn't account for potentially unassessed health issues in some participants, or changes in people's exercise trends over time.

That said, the results echo similar findings from a 2011 meta-analysis published in the journal Circulation. This review of 33 studies concluded that there was a stronger link between exercise and lower death risk in women than men.

The researchers behind the 2024 study hope their findings could help motivate more women to exercise, whether through traditional "cardio" or muscle strengthening regimes including bodyweight exercises or lifting weights.

"I am hopeful that this pioneering research will motivate women who are not currently engaged in regular physical activity to understand that they are in a position to gain tremendous benefit for each increment of regular exercise they are able to invest in their longer-term health," Dr. Christine Albert, chair of the Department of Cardiology in the Smidt Heart Institute who was not involved in the study, said in the statement.