The Exercise Blueprint for Longevity

Living long is a "survival of the fittest."

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I like to run. I don’t really like to lift weights.

If you’re anything like me, you also have a type of exercise you prefer and one you’d rather do without.

While it’s important to do the things we like, there’s no denying that I’d be better off engaging in a bit more strength training each week. That’s what the data say, at least. Aerobic and resistance exercise in isolation lead to profound health benefits, but when combined, are a potent health-promoting cocktail.

The biggest question surrounding exercise doesn’t appear to be “what” to do, but rather “how much” to do and “how hard” to do it. Are the benefits of exercise for reducing the risk of death and disease limitless, or is there a plateau one eventually reaches at the higher ends of the activity spectrum? Is it better to workout harder for longer or accumulate a high volume of low-intensity activity?

Because so many meta-analyses and other studies have been published in recent years on this very topic, we don’t have to guess. Here’s what the science says about the best type and amount of activity for health and longevity.

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The optimal dose and intensity of exercise to reduce mortality ⏰

One of the first studies to evaluate the links between leisure-time physical activity duration and intensity with all-cause mortality and cause-specific mortality was the Harvard School of Public Health study, which included 116,221 individuals who were assessed over 15 times during a 30-year follow-up period. The study concluded that higher levels of long-term leisure-time vigorous and moderate physical activity achieve the maximum benefit of mortality reduction. 

However, the relationship between the dose of exercise and the risk of death during follow-up were different for vigorous activity and moderate activity.

For optimizing long-term cardiovascular health and overall longevity, more is better for moderate activity.

On the other hand, optimal benefits for vigorous activity are achieved at approximately 150 minutes/week. Very high levels of moderate activity reduced the risk of cardiovascular disease mortality and all-cause mortality substantially better than very high levels of vigorous activity did.

Furthermore, moderate activity reduced cardiovascular disease (CVD) mortality and all-cause mortality in a dose-dependent manner — the higher the dose of activity, the lower the number of deaths during the study. Not so for vigorous activity. In doses >150 minutes/week, vigorous activity was associated with a plateau in all-cause mortality, and a modest but progressive loss of CVD mortality reduction (slight reverse-J curve) at higher doses. In other words, the benefits of vigorous exercise appear to have a limit.

Therefore, for individuals who want to decrease the risk of CVD and boost life expectancy, a consistent routine of high-volume moderate-intensity exercise appears to be appropriate. 

Interestingly, chronically performing very high doses of vigorous activity may attenuate some of the benefits bestowed by less extreme efforts, but it’s still important to note that vigorous activity substantially reduces all-cause mortality and CVD mortality compared to a sedentary lifestyle (i.e., doing nothing). Nonetheless, the magnitude of the mortality and CVD risk reductions with high doses of vigorous activity does not appear to be as substantial as for high doses of moderate activity.

Longevity is a “survival of the fittest” 🫀

When it comes to predictors of lifespan, maximal aerobic capacity (VO2 max) is perhaps one of the best. Studies have shown that the best survival rates are observed in individuals who attained a peak exercise level of 14 metabolic equivalents (METs) on a graded exercise test to exhaustion — equal to a VO2 max of about 50 ml/kg/min. In addition, there was no increased risk of premature mortality in the most fit cohort, suggesting that “fitter is better” when it comes to reducing your risk of death.

However, being in the least fit cohort carried a greater mortality risk than any other traditional risk factors, including age, diabetes, smoking, chronic kidney disease, hypertension, atrial fibrillation, obesity, prior CVD, and cancer.

Let’s underscore that finding: having a low VO2 max is a greater risk factor for all-cause mortality than having diabetes, obesity, cancer, or engaging in smoking.

An updated meta-analysis of 37 studies with nearly 2.3 million participants and nearly 110,000 deaths supported the prognostic importance of aerobic fitness for longevity, finding that every one-MET (3.5 ml/kg/min) increase in aerobic fitness was associated with an 11% reduction in mortality. Individuals in the highest tertile of fitness had a 45% lower mortality compared to those in the lowest tertile of fitness, further implicating aerobic capacity as one of the strongest predictors of survival.

How should one go about improving their fitness? What is the best type of exercise to increase VO2 max?

As mentioned earlier, large amounts of moderate exercise seem to be better than large amounts of vigorous exercise for reducing mortality and CVD risks. However, vigorous exercise produces higher levels of fitness than moderate exercise. HIIT seems to be more effective than zone 2 exercise, for instance.

In addition to exercise, many other factors determine one’s fitness, including general health, genetics, nutrition, and body composition. CVD risk factors like obesity, smoking, diabetes, hypertension, chronic kidney disease, and overall disease burden are progressively more unfavorable going from the most fit to the least fit categories, which may suggest that maintaining high fitness is easier for a normal-weight, non-smoking person with favorable genes who is eating well and following a generally healthy lifestyle, even if they are not performing large volumes of vigorous exercise. This idea assumes that VO2 max is more influenced by environment and lifestyle and less by training, a topic that is the subject of debate.

In fact, the contrary could be (and likely is) true: people who are normal weight and follow a generally healthy lifestyle attained their high aerobic fitness via their exercise and healthy lifestyle.

Nonetheless, exercise will improve CVD risk factors such as body composition, blood pressure, blood glucose, chronic inflammation, and bone health, and these benefits are conferred by both moderate-intensity and vigorous-intensity physical activity. In other words, even if VO2 max isn’t highly trainable, exercise reduces other risk factors for mortality.