Has there been any studies on the correlation between the two? How does one know when to stride more or open his stride? Any information would be appreciated.
Has there been any studies on the correlation between the two? How does one know when to stride more or open his stride? Any information would be appreciated.
My stride rate is always the same (a little over 180 strides per minute) and my stride length opens up when I'm running faster and shortens when I'm running slower. I don't chose to always run at the same stride rate I just do and I don't chose to open my stride I just speed up and it happens naturally. If you haven't been running for a long time your stride rate will increase as you continue to run more and do faster pace work.
At any pace the two are perfectly negatively correlated. The determination of what is best for an athlete depends on several factors. I am not an expert on this, but those factors include: 1) pace; 2) natural/trained ability to turn over fast; 3) incline; 4) height and leg length; and 5) type of footfall.
I am 5'11" and when I was running the Pasadena Marathon as a training run I was running next to Micki Gorman, who was doing the half. We knew each other slightly (she was at a brother's wedding) and talked a little as we ran together for several miles until she turned when the 1/2 split off. We were running 5:45 pace or so and she was going after the Masters WR in the Half I think (this was a year or so after she won NY, I think). We were going stride for stride that entire time -- she is 4'11".
From my observations, most ordinary (not top-level and not 9-minute types) tend to run 83-87 strides (L&R) per minute, with higher cadences when they are trying to run fast (these values are for standard runs, not tempo runs, speed, or races.
Some run at a higher frequency and some at a lower one, but too low and you are having to 'bound' into the air and are spending too much energy going up and down. Too fast and you are taking choppy strides and will not be smooth without good training.
Jeremy Wariner's stride frequency is also about 180, but of course his stride amplitude is huge. Michael Johnson's was above 190 but a slightly shorter stride. Most short sprinters are just above 200 spm. So you can see from this the true separation between runners regarding speed is less leg turnover as it is stride length. It takes a lot of pure strength to hold a long stride. This is the basis I use to teach pure speed and it seems to work quite well. Through drills you can teach almost anybody to move their feet at 180 spm and it is then a matter of developing more strength to develop pure speed. Here of course some runners are simply able to get stronger than others. There is a variety of variables in the mix to gain this added strength. Most of these variables are biomechanical in nature.
So the point is that there is little difference between distance runners and sprinters when trying to improve speed. It is simply a matter of degree.
By the way the way you make yourself open the stride for acceleration is to pull with the arms.