Can High-Volume Exercise Be Bad For Your Heart? It Depends On Your Sex

Endurance exercise has often been questioned for its potential to increase heart attack risk, a large (n=61,150) comprehensive (a meta-analysis of studies) research has shown, in a nutshell:

• In men, high-volume endurance exercise is associated with higher coronary artery calcium (CAC) scores (that’s bad) and higher calcified plaque volume (also bad) compared to non-athlete men.
• In women, however, no such increase was found (for CAC or plaque) regardless of exercise volume.

In fact, high-volume female athletes* had less calcified plaque than non-athlete women.

*as in, the exercise was high volume; the volume of the athletes themselves was not mentioned!

You may be wondering: does this mean that men should skip the exercise?

And the answer is: no, because moderate exercise was linked to lower calcified plaque volume in men and women.

As to what “high-volume”, “moderate”, and “non-athletes” mean, for the purposes of the study:

• High: >3,000 MET-minutes/week
• Moderate: 1,500–3,000 MET-minutes/week
• Non-athletes: <1,500 MET-minutes/week

MET = Metabolic Equivalent of Task, i.e. the number your phone exercise tracker app shows, whereby if you exercise for 1 minute with your heart above a certain percentage of its maximum, the tracker records it as 2 minutes, because it is the metabolic equivalent of 2 minutes at the lower heart rate.

Thus, in terms of practical advice: the researchers make clear that they don’t want to discourage exercise ,but to support comprehensive risk assessment, especially in men doing high-volume exercise.

You can read the paper in full here: Sex Differences in the Impact of Exercise Volume on Subclinical Coronary Atherosclerosis: A Meta-Analysis

“I’m a woman without a man in my life, so is this irrelevant to me?”

It might be, or it might not be! The question the researchers didn’t ask is: what’s the current state of your hormones?

Because, in this paper…

Let’s do a quick tally of how many times certain words are mentioned (bearing in mind that the paper is about sex differences, and is 8,301 words long):

• Hormone: 1
• Testosterone: 1
• Estrogen: 0
• Menopause: 0
• HRT: 0

Do you see the problem? An entire paper about sex differences, and we’re still getting medically sidelined.

And, this is likely important, because hormones make a huge difference to heart health; see for example:

• What Menopause Does To The Heart
• Hormones & Health, Beyond The Obvious
• His & Hers? The Hidden Complexities of Statins and Cardiovascular Disease (CVD)

What this means: it is likely, but not known for sure, that sex hormone differences are what affect the coronary artery calcium and calcified plaque scores so drastically as seen in the study.

In practical terms: if you are a woman who is post-menopause and not on hormone replacement therapy (HRT), you could well have higher risk factors in this case.

Want to learn more?

If you’re curious about the current state of your arteries, then please do book a professional test, but meanwhile:

Try This At Home: ABI Test For Clogged Arteries

Take care!