July 28th, 2014

Running: Any Amount Is Good and More May Not Be Better

Although there is broad agreement that exercise is beneficial, there has been substantial uncertainty about how much exercise is good for you. Recently some studies have suggested that too much exercise may actually reduce the benefits of exercise. Now a study published in the Journal of the American College of Cardiology finds that even a small amount of exercise, even running for as little as 5 minutes a day, may be just as healthful as more exercise.

Analyzing data from more than 55,000 adults participating in the Aerobics Center Longitudinal Study, researchers found that, when compared with people who did not run, runners had a significantly reduced risk for both all-cause and cardiovascular mortality. There was no significant difference based on the distance run each week, or other measures of duration, speed, or frequency of running. The researchers report that runners at all levels had a 30% reduction in the risk for death and a 45% reduction in the risk for cardiovascular death, resulting in a 3-year increase in life expectancy.

The study “may motivate more people to start running,” say the authors.

In an accompanying editorial, Chi Pang Wen and colleagues write that despite the observational nature of the study, “the direct health benefits of exercise are irrefutable. The reality is that a virtuous cycle exists for an iterative process of incremental exercise promoting incremental health, and the healthier individuals in turn being more likely to exercise, blurring the simple cause-and-effect relationship.” They advise physicians to offer a simple exercise prescription to patients: “15 min of brisk walking or 5 min of running is all it takes for most clinic patients. Exercise is a miracle drug in many ways.”

2 Responses to “Running: Any Amount Is Good and More May Not Be Better”

  1. Alexander Madaus, MD, phD says:

    I think the results of this study are interesting, but should not be overestimated. The fact that physical exercise has positive effects on many metabolic pathways and the cardiovascular system is without question. But this study has in my opinion left too many questions unanswered. Diet and lifestyle as a whole were not assessed. Only mortality but not morbidity was reported, but we know that exercise is beneficial for the course of many diseases. We don’t know anything about training modalities, e.g. were the “short-time-runners” practicing HIIT?
    To significantly change inflammatory markers more time for (vigorous) exercise is needed than 5-10 minutes, so these findings are not consistent with the known facts concerning manipulation of inflammatory pathways.
    But what concerns me most is the fact, that these findings will serve again for a lack of self-responsibility for many people. We as doctors should emphasize that daily activity (micro- and macro-activity) should be a central matter in everyones life. It is not only about mortality but about quality of life. People loose agility, mobility, strength, coordination and energy through the consequent avoidance of every “unnessecary” movement. This leads to an enormous loss of quality of life, starting at the late 40’s. I train healthy people (that would exactly fit into the collective of this study) around this age, and they are mostly incapable of simple coordinative movements and do not have enough strength to perfom simple tasks as one pushup. Telling these people that 5 minutes of slow running per day is enough to make them healthier is not enough. And we should not rely on studys like this to have a reason to avoid annoying discussions with our patients. It is our duty to point the finger directly to the active self-responsibility for ones health. And it’s not about finding time – it’s about making time.

  2. Karen Politis, MD says:

    Besides the benefits for the cardiovascular system, increasing muscle strength improves balance and helps to avoid falls, which cause so much morbidity in the elderly.