I’m having a problem keeping my hip up and pushing it forward when sprinting. It looks as if I’m in a sitting position when I run.
My abs should be strong enough, but I think my leg flexibility might be poor (the distance between my knees in a full stride is too short). Could that be the cause? If so, what is the most efficient way to improve it?
You want to keep your posture tall and stand up proud like a soldier. The hip height comes from the downward force generated by the leg/foot hitting the ground. There is no pushing the hip forward, and again the “up” part to the hip comes from forcing the leg/foot “down.” Any sort of pushing will result in a longer ground contact time. SPrinting aims to keep the ground contact time as short as possible while generating the most force down into the track.
If you are sitting while running it could be that you are attempting to lift the knee to high (which is very noticable when doing A drills at a slower speed). I have found that if you increase hip mobility and allow the rotation of the hip to increase around the axis of the spine almost all of the knee lift can occur from the recoil of foot off the track and the natural movement of the hips. So now you are in a position where all you need to do is attempt to stay tall while you run and the rest will follow. However, without this hip mobility you are going to be struggling to conciously achieve this. Remember… what is technically desirable must be physically possible!