A study published in July 2014 in the Journal of the American College of Cardiology finds that even 10 minutes a day of low-intensity running is enough to extend life by several years, compared with not running at all. It shows that the minimal healthy “dose” of exercise is smaller than many people might assume.
Take five to stay alive
The new study focused on a group of more than 55,000 men and women ages 18 to 100. About a quarter of them were runners. Over 15 years, those who ran just 50 minutes a week or fewer at a moderate pace were less likely to die from either cardiovascular disease or any cause, compared with those who didn’t run at all.
The study emphasizes the minimum level of exercise to experience health benefits. However, there is no linear relation. That means you can’t run 24hs a day and live forever. So what is the optimal balance between time and results? A study from 2013 suggested that sweet spot is about 2.5 hours per week. A good way to tack these hours to your weekly schedule is to break it into 2 days of 45 minutes and 2 days of 30 minutes. So you can space those 4 sessions during the week depending on your schedule. This will allow flexibility to adjust for days when you are not feeling well or have limited time.
Keeping the total weekly time is important so you can adjust based to your fitness and condition. For those not very fit or just starting, running 30 minutes non-stop is a challenge, even at slow speeds. Then, 45 minutes is a total nightmare. That means that you should alternate walking and running for the duration of the workout. Start at 5 minutes walking followed by 5 minutes of running. Then focus on eliminating the middle 5s so you can walk 5, run 20, walk 5.
This who are more in shape should focus on more demanding workouts such as tempo runs, speed training and hill intervals.
The most important aspect of this training is to develop a habit and keep the weekly hours.
Although running can trim away some of your existing risk of cardiovascular disease, it doesn’t entirely eliminate it. The combined effect of lifestyle, diet, and family history still contribute to your lifetime risk.
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This study used preventing death to measure the benefit of running, but it’s not the most typical reason for running. “Many dedicated long-term runners do not run because they want to live longer,” Dr. Baggish notes. “They run because it makes them feel better on a daily basis. There is a mood elevating, quality-of-life benefit that comes from being a regular exerciser.”
For regular runners, the cost of feeling good can be strains and sprains, so Dr. Baggish advocates for the value of what he calls “active rest.” His rule of thumb, not supported by any specific research, is that it’s a good idea to spend 25% of exercise time over the course of a year running at a lower level of intensity or doing other activities like swimming or biking.
“The body responds to training, but to preserve that benefit over the long haul there needs to be active periods of recovery,” Dr. Baggish says. “Pulling back allows the body to repair and heal.”