Mike Trees on Instagram: "Timing is not often discussed, by coaches, but is soooooo important. It can separate the good from the really good and the poor runners from the good. But more importantly, it can separate the injured from the uninjured. Here we see @paigepenrose_ who was suffering shin splits because she was stabbing the ground. This is very common when runners let their shoes absorb all the impact shock, when their foot lands. I often say it’s a hip or knee surgery waiting to happen,