When you rotate your running shoes, you’re not really extending the life of the shoe, though the amount of time it takes you to run through a pair is longer. The big deal is that you’re saving your legs. See, when you wear shoes of different weights, different offsets, different flexibilities, your feet and legs go through slightly different motions and the feedback from the ground changes–the input changes. And that’s how you save your legs and keep injury at bay. Especially for those of us who run the same loops on the same roads day after day–change it up! Can’t decide if you want a traditional trainer? Maybe something lighter and lower to the ground? Maybe a racer, just ’cause? The answer is yes. All of them. The more often you can change the input–the signals to your soft tissues–the more likely you are to stay healthy.