Dr. Rhonda Patrick: The biggest headline from this study was that vigorous-intensity physical activity was not only twice as effective as moderate-intensity activity. Depending on the outcome, it was associated with effects that were four times to almost 10 times as large.

For all-cause mortality, one minute of vigorous-intensity physical activity was equivalent to about four minutes of moderate-intensity activity. All-cause mortality means death from all non-accidental causes. Vigorous activity gave people a bigger bang for their buck and was about four times as potent for reducing all-cause mortality risk in these models.

The difference was even larger for cardiovascular mortality. This is important because cardiovascular disease is the leading cause of death in the United States and many other developed nations. For each minute of vigorous-intensity physical activity, you had to perform 7.8 minutes, or almost eight minutes, of moderate-intensity activity to get the same modeled reduction in cardiovascular mortality.

If you spent 75 minutes running, cycling, or doing another vigorous exercise, you would have to multiply that time by almost eight to estimate the amount of moderate activity associated with the same cardiovascular mortality benefit. That is huge.

Another major outcome was type 2 diabetes. For every minute of vigorous-intensity physical activity, you had to spend about 9.4 minutes doing moderate-intensity activity. Vigorous activity was almost 10 times as potent for reducing the risk of developing type 2 diabetes.

That is not entirely surprising because exercise intensity drives many metabolic adaptations, including improvements in insulin sensitivity and blood-glucose regulation. But an almost 10-fold difference is still striking.

The last major comparison was cancer mortality. For every minute of vigorous-intensity physical activity, you had to spend about 3.4 or 3.5 minutes doing moderate-intensity activity to get the same modeled reduction in cancer mortality. The physical activity guidelines therefore appear to underestimate the association between vigorous activity and each of these health outcomes.

If people thought about exercise this way, they might get more of a reward response from vigorous workouts. They could think, "This is doing something beneficial for my overall health and the way I age."

Brady Holmer: This may be something we discuss later, but these findings could and probably should change how wearable-device companies program their algorithms and gamify physical activity. They could enhance the rewarding aspects of the activity a person is doing.

Dr. Rhonda Patrick: Definitely. We should discuss that. Before we get there, the difference between vigorous and light physical activity is even more striking. You cannot ignore the time efficiency of vigorous physical activity.

Brady Holmer: Some of these numbers were incredible. The health-equivalence ratios for light activity were extreme. Across the main outcomes, including cancer, one minute of vigorous activity was equal to 53 to 94 minutes of light activity. To get the same mortality risk reduction associated with one minute of running, for example, a person might need about an hour of gentle walking.

Dr. Rhonda Patrick: Pause for a moment. One minute of vigorous physical activity was equivalent to about an hour of gentle walking.

Brady Holmer: That is time-efficient. For diabetes prevention, the estimate was nearly an hour and a half. Ninety-four minutes of light activity was equal to one minute of vigorous-intensity activity. For cardiovascular outcomes, the estimates were 73 minutes for cardiovascular mortality and 86 minutes for major adverse cardiovascular events.

Cancer mortality had the largest estimate. One minute of vigorous activity was equal to 156 minutes, or nearly two and a half hours, of light-intensity activity. Those numbers seem extreme, but that is what the data showed.

The results suggest that even vigorous, purposeful efforts at Zone 2 or above, and not only high-intensity interval training, have an outsized association with health outcomes compared with light-intensity activity. This does not mean light activity is useless. Any movement is better than sitting around.

The study found some benefits from more light-intensity activity for all-cause mortality and diabetes prevention. For cardiovascular mortality, stroke, and heart attack, however, doing more light activity did not produce a significant additional risk reduction. The reductions were around 5% to 10%, which the authors did not consider meaningful in this study.

The authors wrote that not even the largest amounts of daily low-intensity physical activity could elicit the health benefits of moderate- or vigorous-intensity activity. That was an apt conclusion.

Dr. Rhonda Patrick: I agree. I remember the paper showing that the benefit from light physical activity was capped around a 15% reduction for cardiovascular mortality and some other outcomes, with perhaps a 10% cap for cancer. Even after hours of light activity, the association did not continue beyond that level.

Brady Holmer: There was not a potent dose-response relationship for light activity.

Dr. Rhonda Patrick: Vigorous-intensity physical activity did show a dose-response relationship. Before discussing that, I forgot to mention the risk of a heart attack or stroke. For every minute of vigorous activity, about 5.4 minutes of moderate-intensity activity were needed to get the same modeled reduction in those major adverse events. Vigorous activity could be much more time-efficient than moderate activity, and certainly more time-efficient than light activity.

I do not want to dismiss the point that being sedentary is harmful. Sedentary behavior is an independent risk factor, particularly for cancer. Was cancer one of the outcomes for which light activity showed more benefit?

Brady Holmer: The clearest benefits of light activity were for all-cause mortality and diabetes. Cancer had the large equivalence estimate between light and vigorous activity. It was 156 minutes of light activity for the modeled risk reduction associated with one minute of vigorous activity, but there was no dose-response relationship for light activity and cancer.

Dr. Rhonda Patrick: Being sedentary is bad, so anything that makes a person less sedentary is better. But if we are talking about being physically active, I think we should discuss at least moderate and preferably vigorous activity.

Vigorous activity does not even have to be as intense as the high-intensity exercise we often discuss on this podcast. I talk about the benefits of high-intensity exercise for the brain and its time efficiency. Here, vigorous activity has a wider intensity range.

Brady Holmer: That is liberating because we are not saying a person needs 300 minutes of high-intensity interval training with the Norwegian 4x4.

Dr. Rhonda Patrick: The Norwegian 4x4.

Brady Holmer: Exactly. Even that amount of Zone 2 exercise is beneficial. A person does not need to do high-intensity interval training constantly. Purposeful movement at a Zone 2 intensity can still have incredible benefits.

Dr. Rhonda Patrick: We are dramatically underestimating the power of exercise and getting the heart rate up. The study did not measure activity by heart rate, but the measures do correlate.