Running studies have made a variety of claims from life extension, to being good for the knees and even potential heart issues. Angela Chen a runner and writer over at The Verge sums up how to interpret the studies and figure out which ones apply to yourself. She suggests matching the study participants to your own demographics and training level.
So how can you tell if a study’s results might apply to you? First, look at the demographics of people who were studied. Are they similar to you in terms of age and sex? What about their activity level — were the people sedentary and non-active in the beginning, or lifelong runners? Good studies on running will also provide information on how much someone exercised before the study, which usually includes mileage per week and a pace, so you can compare even more accurately. And treadmill running, which can often use different inclines, versus trail training sometimes have different effects, too. The more similar you are to the participants, the more you can apply the results. So a study about older men who run for five hours a week on a treadmill might not give me the most insight into what makes sense for me, a young woman who would rather never move again than run on a treadmill. (If this information isn’t provided in the write-up you’re reading, it’s usually in the abstract of the study itself, which is usually linked in an article.)