If you had to only focus on one element of running form first it should be this:
When focusing on stride rate we can count the number of steps we take each minute while running at a steady pace on a flat surface (note: it is easiest to do this by counting how many times one foot hits the ground over 60 seconds and then multiplying that number by 2).
What many coaches and exercise physiologists have found is that a stride rate of about 180 steps per minute (give or take 5-10 steps) is the optimal stride rate (or frequency) for efficiency at paces from your Easy aerobic conversational pace (or even ultra race pace), to about as fast as all-out 10km race pace. If you were doing a short sprint or a race shorter than a 5km it is likely your stride rate would probably exceed or at least approach 200 steps/minute though.
But the 180 steps/minute frequency stands fairly true at a broad range of paces that we (as ultra runners) tend to race and train at! There is some individual variation, and changes with uphills (where stride rate tends to slow maybe even down to 160) and downhills ( where stride rate increases), but generally most people should work on their stride rate if they are below 165-170 steps per minute (we say 165-170 because of individual variation as some people may really struggle hitting 180 exactly and we figure that 170 is close enough).
Why is stride rate so important?
Well, having a stride rate at this frequency essentially ensures that you are not over-striding and that you are quick and light on your feet. It is harder to heel strike as you are forced to land more quickly under your center of gravity. Vertical oscillation, or the distance you spring up in the air, becomes reduced and more energy efficient with this kind of stride rate. Furthermore, this light and quick cadence also ensures that your foot-ground contact time is reduced and the impact force of each stride is also not as hard!
All these things that basically ensure a proper foot strike (which we really shouldn’t focus on very much!) can be taken care of just by getting one’s stride rate up over 170 steps per minute.
So with our stride rate relatively constant at 170 to maybe 190 steps per minute at most training to racing paces, the only variable that changes much with faster running velocity is our stride length.
This is why when you watch the elites at a marathon running under 5:00 per mile pace they don’t look like they are sprinting. They are likely running with a similar stride rate as you are, but their stride length is huge! To be able to increase one’s speed we need a longer stride length - and in order to do that, we need to have the cardiovascular engine to support such work/power output. But we also need the leg strength/push off force and proper mechanics to ensure efficiency.
When looking at the element of mechanical efficiency in our Sage Running Form™ we see that hip mobility, drive, and extension, play a huge role in developing an “ease of speed.”