Few people would ever consider pushing the limits of their endurance like Ben Lecomte, the first person to swim across the Atlantic Ocean. Now he’s planning to swim across the Pacific Ocean, from Tokyo to San Francisco — a wet and lonely 5,500-mile journey that will take about five or six months to complete.

As reported by NPR:¹

“Lecomte, who lives in Austin, Texas, is diving back into the ocean to focus attention on environmental problems …. During the swim, he will collect data on the Pacific, including the microbes and trash he encounters.

People can follow along on his Facebook page,² ‘The Longest Swim.'”

This is the epitome of extreme exercise, and cardiologist Dr. Benjamin Levine, director of the Institute of Exercise and Environmental Medicine will study Lecomte’s heart and health during this event.

To do that, he’ll be using the same technology NASA uses to monitor the health of astronauts on the International Space Station.

Chances are Lecomte will damage his heart to some degree, because contrary to popular belief, more does not necessarily equate to better health when it comes to exercise. There’s a “Goldilocks zone,” beyond which the damage incurred outweighs the benefits.

Exercise Is Good Medicine at the Right Dosage

Modern fitness research offers many potent reminders that physical activity is one of the best “preventive drugs” for many common ailments, from psychiatric disorders to heart disease, diabetes, and cancer.3

For example, one meta-review⁴ of 305 randomized controlled trials comparing the effectiveness of exercise versus drug interventions on mortality outcomes found “no statistically detectable differences” between exercise and medications for prediabetes and heart disease.

One of the key health benefits of exercise is that it helps normalize your glucose, insulin, and leptin levels by optimizing insulin and leptin receptor sensitivity. This is an important factor for optimizing your overall health and preventing chronic disease.

Another way in which exercise promotes good health and longevity is by forcing your mitochondria (those little “power stations” inside your cells that produce energy or ATP) to work harder, thereby producing more mitochondria (biogenesis) to keep up with the heightened energy requirement.

A side effect of this is a slowing down of your biological aging process.

However, as with other medications, there’s the matter of dosage. Too little exercise and you won’t get much benefit. (Worse yet, chronic inactivity has been shown to be an independent risk factor of chronic disease and early death.)

On the other hand, exercise too much, and you could do harm. As noted by Dr. Levine, while endurance athletes live longer than non-athletes — in general, nearly 20 percent longer than non-runners — the evidence also shows that going overboard does put your health at risk.

One of the risks of excessive high intensity cardio is you can develop enlargement of your heart that leads to something called diastolic dysfunction which can lead to heart failure and is really an epidemic in the U.S.