I was recently working with a group of middle distance runners and one of them told me he was having trouble “holding his form” when he got tired. He said he would try to keep his good posture but eventually it would fall apart.
I explained to him that posture is an irrelevant concept in running and he shouldn’t try to hold onto anything. Everything moves when you run. And not just forward in space like you’d expect, but also in relation to your other parts. Trying to maintain a “posture” or to hold anything anywhere isn’t good form, it’s interference with the action of running and it costs you a lot of effort because you’re basically fighting yourself.
An example of this is the idea that you should hold your shoulders back. This is bad for your running because your upper body turns when you run and your arms swing, one forward and one backwards. Your shoulder girdle also moves as part of both the rotation and the swing of your arms. So if you pull both shoulder blades back you interfere with the rotation of your upper body – thus increasing your effort, your impact, and the stress on your feet and legs – and you interfere with the movement of your arms, which disturbs your shift of weight from leg to leg, unbalances your spine, and increases your overall effort.
It’s true that there is such a thing as excessive movement; any part that can move can move excessively and that wastes energy and disturbs your balance of effort. But when we work with runners we don’t look for where they’re moving excessively and try to have them restrict that movement. Instead we look for what isn’t moving enough or properly and help them feel how to improve that, and as a result they naturally down-regulate their excessive movement (be it armswing, pelvis movement, or something else) without even trying. When every part of your body moves as it sufficiently, nothing is forced to move excessively.
When you run, instead of trying to maintain good posture ask yourself instead whether everything is moving as it should. And when you start getting tired, use that fatigue to help you find the places where you could stop fighting yourself and relax into your running.