Can Fitness Conquer All?

My work affords me the opportunity to call some of the most recognized clinical exercise physiology researchers in the world colleagues. And lucky for me, not only do I learn from them, but I am also able to collaborate on research; spending hours upon hours reviewing medical charts for thousands of veterans receiving their care at our hospital or sitting in an office on evenings and the occasional Sunday reviewing statistics. No one ever said research was glamorous.

It is now well established, with over 650 million person-years of follow up, that cardiorespiratory fitness is the best predictor of mortality risk. The higher your fitness, the healthier you are and the longer you live; no matter what other medical conditions you might have. This month we published research (Faselis et al., Am. J. Htn) exploring whether the mortality risk of veterans with high blood pressure was affected by their body mass index (BMI) and their fitness level.

Being overweight and obese increases the risk of having high blood pressure, as well as developing other chronic conditions that increases risk of premature death. We looked veterans who had undergone a peak treadmill stress test. During these tests you’re asked to walk, possibly jog, on the treadmill as the speed and incline increase progressively, according to a determined protocol, until you cannot go any further. The highest workload, achieved at the very end of the test, determines how physically fit someone is.

We found that the higher someone’s fitness level, the lower his risk of dying, regardless of BMI. Compared to people whose peak exercise capacity was approximately the same as being completely out of breath after climbing a flight of stairs (
What is most interesting is that obese high-fit veterans lived longer than normal weight high-fit veterans, although we are unsure why. Obese veterans were younger, had better blood pressure control, and used more medications than their normal weight counterparts. Perhaps obese veterans sought out medical care sooner or their providers were more willing to prescribe medications to help them control chronic disease risk factors like high blood pressure, blood sugar, or cholesterol. This veterans’ obesity paradox has been observed in other research and is still being explored.

But ultimately, the take home message of our work is that getting on the elliptical or in the pool, on the bike, or going out for a walk or run regularly for at least 150-200 min./week could be considered the most important thing we can all do for our health, no matter our weight or risk factors.