What running shoe should you buy?
Well, the marketing research is clear. People buy shoes b/c of 1) color, and 2) “first feel”. First feel is that first step you take. You know that sense of walking on a cloud…..the same feeling that made you think you could stand around in them for hours? Well, that doesn’t have anything to do with running shoe selection. Running is not standing. When you stand, you have half your body weight split between each foot. The total load on each each leg is about half your body weight. When you walk, sometimes you have two feet on the ground, and sometimes you have one foot down on the ground. So at the most, you’d have your full body weight on one leg, and at the least, it would be split between both legs. And when you are walking, your feet are on the ground for a long time. If you need to “micro-correct” your muscles to stabilize your body, you’ve got time to do so.
Running isn’t standing. And its not walking. During running, your foot is only on the ground for a very short time: The average runner moving at 7.2 mph is on the ground for only .17 seconds. Decisions on stability need to happen very very quickly, faster than you can actually think about them. And when running, there is no double leg contact. You are either sailing through the air, or in contact with a single leg. That single leg must not only support your full body weight, but about 2.5x’s your body weight.