Think quick. Think low. Think short, swift movements.
If you’re trying to run fast, I’ve talked about how most fall into the trap of longer, lunging strides… instead of shortening up enough to where they can turn their feet over more quickly. The latter will cover more ground in the long run, and is a much more comfortable way to run faster than usual.
When starting your run, begin with a trot, and gradually accelerate the turnover of steps in that trot.
Many also fall into the trap of swinging their arms far too much, extraneous movement that wastes energy and not only tires you out more quickly but slows you down.
The only directions your arms should drive is back. Your arms should naturally repel back forward, allowing you to drive them back once again. In fact, and this is admittedly from various running form texts, your arms should ideally not swing in front of you at all. The farthest forward your elbows should come is right beside your obliques.
And your arms ought to be low, and stay low. Yes, I’ve seen (and know) plenty of runners who run comfortably with their arms high in front of them. Like a baseball pitcher with a high leg kick, it’s a quirk that works well for some and their style. For most, the most efficient form for your arms is low and driving back while not propeling far forward.
A good way to think about running is to run with the feel a hovercraft… or like a plane taxi-ing along the runway. The latter glides along the pavement, occasionally firing the engines just a little bit, enough to move itself forward.
If you’re not sprinting, look to find a rhythm that feels like you’re briskly gliding low along the pavement. Your legs aren’t lifting too high with each step. Your arms are low to the ground. Your steps are smooth, swift, so short and imperceptible that if you didn’t know any better you’d swear you had no legs and were in fact gliding like a hovercraft.
This smooth rhythm also making slowing down or stopping for obstacles easy and seamless, as well as gliding back into your desired pace once you’re running again.
At the very least, it feels a lot better than grunting and pushing out hard steps to try and run fast. You may find smooth is faster anyway.