Stride frequency and pace

If two runners are striding at 180 strides per minute, they will almost definitely have the same ground contact time. They both take 3 strides per second; how could one's feet remain on the ground longer?

Also, that guy who responded about running like Sammy Kipketer sounded a bit fake.

He said he now runs a minute per mile faster on easy runs.

I doubt one could make such a tremendous change from a simple form alteration.

Even at easy run pace, 180 strides per minute is not a bad idea if you are used to it.

After I read DRF, I started to watch tapes of runners from as far back as the 1972 olympics up the present. Guess what, Daniels' observation proves to be correct. I wish people would do their homework. Daniels writes that runners in distances from 3000 and up averaged 180 strides/ minute. He does not give the figures but merely notes that 800m runners had the fastest turnover and 1500m were next fastest. He implies that their rates are higher than 180. And given what he just posted about that female runner, and my own observations, there are competitive elites in these distances as fast as 200 strides/minute. However, the doubters among you should please note that I haven't observed a single instance of someone with a turnover as low as 160. Once I figured this out myself I began counting my own stride rate and found that, yes, my turnover was too slow. Six weeks of easy running with my only focus being to work on turnover was enough to rewire my legs. It's been several years since I thought about it. Every once in a while I do a rate check and find that my turnover has held in the low 180s. So get to work.

Cat Paws wrote:

So if my stride rate is way down on slower pace days, what does that tell me? I'm running too slow? Not enough effort?

I don't mean to be rude, but the initial thing it tells me is that you don't run with "Cat Paw's", which would be light, nimble, and no heel strike. 180 is surely no magical number. However, look at the extremes, how fast could you run a mile taking just 1 step a minute? It'd take a very long time. 2 steps a minute would likely be twice as fast. 4 steps would likely be 4 times as fast. 20 steps would not likely be 20 times as fast however, as having only 3 seconds in between each step/jump wouldn't give you enough rest to be as explosive as having a minute or 30 seconds in between each step/jump. So maybe around 10 steps you start to see a parabolic curve taking shape seeing diminishing returns with each step taken. Now, if you were to try to take as many steps per minute as Michael Johnson (truly a cat) did in the 400, I believe its around 245 give or take a few, you'd likely find you were faster at around 200 or 210. If I were your personal coach we'd figure out at what stride frequency you could cover the most ground in a minute, say for you it's 205. You'd want to do barefoot (another cat like thing that increases frequency) strides on soft surfaces in that 205 or slightly over zone, constantly bringing your control over your muscle/energy firing rate higher. When people push to a higher amount of steps/minute and find it slows them down, I feel this is because they are working more like a DC motor, or direct current system, as opposed to the more efficient, AC or alternating current, which is found throughout nature. (Not sure of the AC/DC stuff?, try reading Nikola Tesla's biographies) Think of the moment you reconnect with the ground as when you turn your muscles "ON", and when you are in the air they are "OFF", though not off meaning you are limp. It's almost as if you are bounding, but hiding it in the form of running. I'm sure when I write a book it'll make better sense than this, but maybe this will resonate with someone. Actually I think I explained it better in the AC:DC :: Kalenjin:American thread, or something close to that title. Sorry for the lack of orginization.

Biaffran wrote:

If two runners are striding at 180 strides per minute, they will almost definitely have the same ground contact time. They both take 3 strides per second; how could one's feet remain on the ground longer?

...

I doubt one could make such a tremendous change from a simple form alteration.

not at all true. if runner A has ground contact time of 200ms, and runner B has ground contact time of 225ms, and they do the same amount of work (by the muscle, as in force applied over a distance = work), than runner A has greater power.

to address your second point, here's an excerpt from the link at the bottom:

"Let's take a moment to put some numbers on this: a reduction in footstrike time of just 1/300 of a second could reduce 5k time by 10 seconds for a 16-minute 5k runner (providing it didn't lead to a loss of stride length), while trimming contact time by 1/100 of a second could lead to a 30-second improvement. Interestingly, the difference in average contact time between the fastest and slowest 5k runners in Rusko's study was about 27 milliseconds (2.7 hundredths of a second), and this difference was associated with a 54-second difference in finishing time.

Rusko was also able to show that stride rate was directly related to 5k speed: the higher the stride rate, the faster the finish time. Since stride lengths were comparable for the runners in his study, it was clearly the decrease in footstrike time which increased stride rate; since this occurred without a drop in stride length, the more-abridged footstrike pattern allowed runners to eat up more road during each minute of running. "

hope that explains things better.

To help clarify a little, it does seem intuitive that stride frequency would correspond directly to the amount of time your foot spends on the ground. But as Greg's link points out, there are other factors that also come into play. Essentially, there's a whole lot more to efficiency than simply counting strides. For example, our favorite guy, Galloway, used to have this 'Daily tip' on RWOL about 'the shuffle.' In it, he asserted that the most efficient stride is one in which the foot barely lifts off the ground and just kind of slides forward very quickly. However, if you look at the lead pack in a race of any distance, you will see that quite the opposite is true -- lots of elastic snap in the vast majority of fast runners, those who I think we agree are most efficient.

Not a negative response, but a comment about the Penn State studies -- the runners were most comfortable at their freely-chosen stride rate, the stride rate they had been practicing all their running careers. When forced to a faster or slower rate it was less efficient, but what if they trained at one of those faster or slower cadences for a few months or years -- could be that the new rate wouldnow be more economical and even become the chosen one. This, of course, is a problem with training studies -- who is willing to change their current turnover for half a year to see if it is better? Reminds me of the foot-strike studies we have done. Most runners prefer rear-foot strike, but some who have done it all their lives become more economical by becoming a fore-foot striker. And some fore-foot strikers are more economical converting to rear-foot striking. Who knows what would be best for any one idividual who trained with a different foot strike for several months. We tested a 2:08 marathoner in different shoes and the shoe he was most economical in (by 2% which is about 2 minutes in a marathon), he refused to wear "don't feel right." was his take. And I would not argue with him because the tests lasted only about 10 minutes and a marathon lasts a couple hours. Who knows what trouble he may have had in the economical shoes over the couorseof a marathon. Gotta go with what feels right

in the next day or so

About the reference to 180 at the 1984 Olympics: Are you sure that this is accurate? Was this during the races or while training? I would guess that the stride frequency of top runners then would be the same as top runners now and when I examined a tape of a meet last year, I found much higher frequencies. It the was meet where the doper Boulami broke his steeple world record. I probably counted strides for about 10 different runners, male and female, and most were about 100-102 cycles per minute (counting boths sides -> =200-204) These were in the 800, 1500, and steeple and 5000 meter races. There was some individual variations, with Boulami at about 110 (220) in the last lap. The sprinters were obviously faster at 137 for Marion and ~145 for Tim.

When I counted strides for myself one time, I found it pretty constant at 92-93 cycles/min at paces from slow (9min/mi) to medium (6-7 min/mi). At other times I have counted something like 88-90 (176-180) when going really slow. I would guess that at racing paces I go up to about 100. By the way, I do get a lot of comments critiquing my short stride, especially when I am going slow. I used to think that it was just a higher cadence that made my stride short, but thinking about it, I think that my range of motion is pretty limited too. I should probably join Gabe Jenning in the quest to open up my thighs...

I do think that higher strides rates are good, but your arguments are less than perfect. Using the extreme of 1 step/min is not comparable as you are not running, you are standing around for most of the time. Instead, imagine that you actually had the power to run at 1 step/min. What would the result be? You'd be floating in the air for nearly a minute and moving quite fast! To achieve that from a single "push" (i.e., basic projectile motion) you'd have to generate a huge "up" component for the take off vector and that means a huge landing force. I have a hard time seeing how that landing force can be good. So as I see it, more steps really means less vertical, which is probably good. (I say probably because even though the magnitude has decreased, the total number of landings have increased.)

What the the heck is this? Do you have any training in electrical theory? This makes no sense to me whatsoever, and I doubt anyone else! I can't find a proper analogy no matter how I stretch it.

As I'm too stinkin' curious for my own good, I did a quick projectile calc. Assuming the body took off at 45 degrees for maximum distance downrange and ignoring air resistance, 1 step/min yields a horizontal velocity component of nearly 1000 feet per second. By the time you landed you'd have traversed nearly 11 miles. 11 miles per minute is kinda quick actually.

Had to do some digging, but did find some of the 84 results. Mean step/min values, which means some were slower, some faster: All are in races ( we looked at prelim, semi, finals and mid-race as well as last 400 and last 200 to see what changed, if anything)

800 Women -- 201, men - - 193 (average test velocities were 458 and 407 m/min)

1500 Women -- 198, men - - 190 (test velocities 390 and 358)

3000 Women -- 190, Men steeple -- 183 (average remember, water jump not included, but barriers were)

5000 Women ----------, Men - - 189 (361m/min)

10k Women -----------, Men -- 185 (347 m/min)

Marathon Women 197 (289m/min, didn't get the men here -- relied on TV)

With good (male) runners at training paces we got means of 178 at 6:00 pace, 180 at 5:30 pace, 183 at 5:12 pace and 185 at 4:52 pace.

I have always sort of concluded that good runners go at 180 or more -- certainly some go considerable faster when racing shorter distances. (from stride rate and running velocity you can calculate for yourself what stride length was). In addition to the above, I almost always count stride rate (and ventilatory frequency) when I test anyone (without telling them I am counting, of course) and get these same values with trained runners, dating back to early 1960s, and as recently as 2003 (An Olympian who wast 6'-6" fell in the same category)

OK. That makes sense. The races that I looked at were run at paces much faster than 4:52, so 200-204 is probably not unexpected, and you do have a couple numbers up near 200, even at the marathon distance. I obviously didn't count strides for the entire races because of poor TY coverage - plus I just wanted a sampling to satisfy my curiosity. Most of counting that I did was off the videos of the final laps. Would this bias the measurement toward a higher rate too? Boulami was just churning...

Looking at the means that you got for good male runners at different paces, I definitely do have a higher stride rate, so I guess that confirms my low stride length.

When we looked at rate and stride length during final laps just about everyone increased length and rate -- some did it different ways. Puica (women's 3000 winner) was the only runner who "kicked" by slowing rate and only increasing stride length. As I remember she had a mid-60s last 400. Always wondered if she trained to increase stride length when increasing speed -- more power, from hill stuff? who knows

Your legs act like a pendulum. The period of pendulum(frequency) is controlled by it's length. The longer a pendulum the slower is swings. A runners stride rate is greatly effected by this. The easiest way to increase stride length is to shorten your pendulum. That is why sprinters run with such a high knee lift. They are shorenting their pendulum so that it can more quickly cycle from the back to front. Try it!! Walk or jog at an easy pace. After about 10 seconds begin to lift your knee up through as your back leg comes forward. You will feel yourself walk or jog faster without a change in effort. This can definitely lead to greater impact at foot plant. Acceptable for a sprinter but not a distance runner. I would be willing to bet that the guy with a 160 frequency was tall.

Sentence 5 from prior post should say stride frequency not stride length.

Jim, I don't think any argument can be perfect, else it wouldn't be open to argument. Taking something to the extreme can help one understand what is at hand and that is the point of starting out at 1 step/min and going as high as something such as 1000 steps/min, even though at this point in humanity that number is only a theoretical one. 1 step/min doesn't count as running by definition, but even running can be classified in the broader category of "unassisted propulsion" or something like that, of which walking, bounding, limping, running, gallowalking, crawling, etc., all would fall under. We're just trying to figure out how to go farther, faster. Who cares what you call it?

So, back to what you have asked and stated. If you were powerful enough to run at 1000 ft/sec, or basically the speed of sound, I doubt you'd be worrying about your impact. The problem would be how would Nike come up with your trillion dollar signing bonus? And why is it people never want to take into account air? Man's terminal velocity is less than 200mph as far as I know.

As far as the AC/DC thing...I have no expertise in the electrical field, (Just something that came to me while reading a biography on Nikola Tesla) however I am owner of a body that has a more complex electrical system than anyone in the electrical field has ever been able to create. When I have an epiphany (sp?) and at the same time my electrical body rejoices by collectively turning on for an instant and sending a "chill" through me, and then the next metal thing I touch shocks me, I tend to trust whatever that epiphany was. So...I do believe, and have no proof once again, that one will run faster as they learn how to pulse their energy into smaller outbursts, which will coincide with the ability to have a higher turnover while staying efficient. People that run "tight", such as clenched fists, are pulsing for too long of a time, in fact some people are almost like one continuous pulse because they are contracting constantly. When people are running super fast it tends to look super smooth, because they are in "off" mode almost the whole time and when they pulse, or are "on", it is extremely fast and for an extremely short amount of time. Other people have measured how long people's feet (though they are generally measuring these people's shoes really) are in contact with the ground. As this number goes down, generally one's overall speed goes up. This makes sense to me as it seems they are pulsing quicker, which means they have better control of their bodies I'd say and have the advantage then of being closer to the "off" state in between pulses which gives them a longer period of relaxation in between pulses, all this plus of course they are on the ground for less time.

As far as analogies of things pulsing to make more energy than doing constant work...you being awake, and then going to sleep...your heart beating, and then relaxing...a two stroke motor...day and night...i don't know what else, but it does seem to be a recurring theme of nature.

Clearly I'm not a poet, else I'd have written this whole thing in a few lines and it would have made even more sense, to the people who already understood it of course.

A man's terminal velocity is what he reaches falling toward the Earth (i.e., the balance between the force of gravity and the force of air friction). That doesn't mean that you couldn't fling one faster. That's academic of course. My point was that your logic didn't work (the technique is called "reductio ad absurdum" and I use it frequently with my students).

As far as the AC/DC thing is concerned, given your admission of no training in this area, perhaps it is best to avoid using it as it may confuse matters. Technically, what you have described in your refinement is normally referred to as "pulsating DC" not AC, and your argument centers around changing the "duty cycle" of the signal. Let's not go there. Intuition is not always to be trusted.

OK, that was waaaay off topic.

Jim,

Why is it again that the logic doesn't work? We would simply be making a graph showing how far one could move using 1 step on up to the highest amount of steps they could take in a minute. Just because it doesn't fall under the term "running" doesn't invalidate the experiment. There was nothing more annoying in school than the teacher who would invalidate students ideas if the teacher had not previously thought of that idea. Don't get caught up in the words, look at the idea behind the words.

You appear to have more expertise in the electrical field than I, as you mention what i'm thinking of is "pulsing DC". Maybe AC would apply if a runner changed direction 90degrees out of nowhere? I thought because the legs hit a certain point and then suddenly change direction 180 degrees that AC was fitting, apparently not. Anyway, our movements are generated from electrical impulses, aren't they? So it would seem understanding electricity would help one understand running better. Please remind me of my stupidity oh hallowed one ;)