If you think running is a waste of time, you might want to reconsider. A new study suggests that one hour of running could elongate your life by nearly seven hours, earning you more time than you spend on the activity.
The review, recently published in Progress in Cardiovascular Disease, is a followup to a different study from the Cooper Institute a few years back. The previous research suggested that even small amounts of running each day could increase life span, but the data left a lot of questions unanswered, which this followup review sought to answer. Most notably, researchers wanted to know how much time you had to put into cardio-heavy activity to get time out of it. For example, to extend your life by an hour, would you have to run for an hour? If so, that would hardly seem worth it to most people.
But after analysing the data, they found something encouraging for all kinds of runners, veteran or beginner. Not only did consistent running seem to drop the risk of premature death by almost 40%, the activity seemed to statistically return more time to runner's lives than it consumed. Say you ran for about two hours every week (which is less than 20 minutes every day). Over the next 40 years you'd spend less than six months of that time doing the activity, but, according to the review, you'd possibly increase your life expectancy by another 3.2 years. That's a net gain of around 2.7 years, or in simpler terms, for every hour you run you lengthen your life by another seven hours (six net).
The longevity benefits aren't without limits, however. As co-author Dr. Duck-chul Lee, professor of kinesiology at Iowa State University, explains, running won't let you live forever. Lee says you cap out at around three extra years, regardless of how much extra running you do over your lifetime, which isn't the best news for long-distance runners who really crank out the miles. The data showed that improvements to life expectancy plateaued somewhere around four hours of running per week. But the good news is prolonged running doesn't seem to be counterproductive either. Runners who went well beyond the average running time each week didn't see any declines in health or life expectancy.
Walking, cycling, and other cardio activity had life prolonging benefits as well, but running seemed to provide the best return of time investment. Lee and his fellow researchers aren't sure why that is, but it may have something to do with how it raises your overall aerobic fitness, and that is one of the best-known indicators for your long-term health.
That said, as with other similar studies, it's important to note that correlation doesn't equal causation. What this data actually proves is that people who run tend to also live longer, but not necessarily that running is the main reason for that. Dr. Lee notes that runners also tend to lead healthier lives in general, so other lifestyle choices, like diet and sleep, likely play a major role as well. Even so, this new data sheds more light on the many perks of cardio workouts, and how you can benefit from them down the road. So lace up those shoes and run for your life.