Over the past week a few posts have popped up on blogs that I frequent regarding the topic of running cadence/stride rate. First, Alex Hutchinson at Sweat Science put up a post titled “The problem with 180 strides per minute: some personal data.” In his post Alex shares some personal data on cadence, and emphasizes that the oft repeated ideal of 180 strides per minute makes no sense since cadence changes with running speed (and I agree). He concludes by saying the following:
“Of course, this doesn’t mean I don’t think stride rate is important. I definitely agree with those who suggest that overstriding is probably the most widespread and easily addressed problem among recreational runners. But rather than aspiring to a magical 180 threshold, I agree with Wisconsin researcher Bryan Heiderscheit, whose studies suggest that increasing your cadence by 5-10% (if you suspect you may be overstriding) is the way to go.”
Alex pretty much sums up my feelings on cadence, and I absolutely agree that 180 need not be some magic number that all runners need to shoot for. In a previous post here on Runblogger I wrote the following:
One often hears the magic number of 180 strides per minute thrown around these days as being the optimal cadence for a runner… I believe this number can be traced back to famed coach Dr. Jack Daniels observation that elite runners tend to run at a stride rate of 180-200 steps/minute. I’m not sure that we have any conclusive data saying that the 180 number is optimal for every person, but Heiderscheit et al. 2011 showed that running with a faster cadence/higher stride rate (5-10% increase) reduced loading on the knee and hip, allowed for a more level carriage of the center of mass (less vertical oscillation), shortened stride length, and created less braking impulse (read my post on the Heiderscheit paper here). All seem like reasonably positive outcomes if you ask me, and this paper might be a useful guide in that a mere 5% increase in you cadence might be all that is necessary to realize some benefit. It turns out that the 170-190 range would probably be where most people would land if they increased cadence by 5-10%.
Shortly after Alex’s post was published, Peter Vigneron put up a post on the topic on the Outside Blog titled Does Form Matter? (continued) – Peter is a former editor for Runner’s World and he wrote the story on running form that appeared in the June issue of RW. In his Outside post, Peter says the following:
But as journalist, physicist, and former elite runner Alex Hutchinson notes, the 180-strides-per-minute benchmark isn’t all it’s cracked up to be. There are serious problems with Daniels’s observations (among them, a small sample size and no analysis of stride length plotted against speed), and other research has contradicted some of its conclusions. More likely, Hutchinson writes, runners play with both stride length and stride frequency when they run, and 180 makes sense at some speeds and not at others. Blogger and Nike coach Steve Magness has made similar observations.
Why is this important? In reporting of the form story, the 180-strides-per-minute rule came up as one of the few objective measures of good form. Nobody said it was the most important measure—if good form exists, it probably has more to do with dorsiflexion angles and knee position at ground contact—but for runners to change form, it helps to know what to aim for. And it’s much easier to count strides than it is to measure dorsiflexion angles, never mind figure out what dorsiflexion means.
Given all of this talk about cadence, I couldn’t help but conduct another experiment on myself. Earlier today I went for a 7 mile run with my Wahoo Fitness footpod stride sensor linked up to my Garmin 305 GPS watch. I ran paces ranging from 10:00+/mile down to sub-5:00/mile, and attempted to hold pace as steady as possible for at least 0.2 miles at each speed. After the run I uploaded the Garmin data to SportTracks, and exported my 100 meter splits for the full seven miles into Microsoft Excel (data for each 100m split included time, speed, and avg. stride rate). Using a little Excel magic, I calculated the exact number of steps and strides taken during each split, and used that value to calculate avg. stride length by dividing 100m by the number of strides taken during that split.
Below are my results. First, plotting cadence in steps/min vs. speed, you can see that my cadence clearly increases as I pick up the pace, from about 178 –179 steps/min at a 10 minute mile pace (6 mph), to 220 steps/min at just under a 5 minute mile pace (12+ mph) – this is a cadence increase of 23%. My easy pace ranges from about 7:30-8:15 min/mile, and that is where you find the biggest cluster of points in the graph below – my easy cadence ranges around 182-184 steps/minute.
It might be tempting to look at the above graph and conclude that I increase my speed solely by increasing my cadence. Not so fast. Next is a graph that I found really interesting. This one shows the number of steps taken per 100 meter split:
What this shows is that although my cadence increases as I speed up, the number of steps that I actually take per 100m declines dramatically. The reason for this is that at my fastest pace I covered the 100m in less than half the time (18.2 sec) it took me to cover the same distance at my slowest pace (38.5 sec). It took me 113 steps to cover 100m at a 10:18 min/mile pace, but only 66 at a 4:52 min/mile pace. In other words, I took a bit over half as many steps to run 100m at double the speed.
To avoid confusion before moving on, it’s important to note that a step is technically defined as the period from landing of one foot to landing of the opposite foot, whereas a stride is the period from landing of one foot to the next landing of the same foot – we typically report cadence in steps/min, but length is typically reported as stride length. Since speed is a function of cadence and stride length, then I had to have been taking longer strides as I increased my speed in order to cover the same 100m distance in fewer steps. Given that I know how many strides I took per 100m, I can put some numbers on this – here’s my stride length (in meters) compared to speed:
What you can see here is that as I speed up, my stride length increases dramatically – from 1.77m at slowest pace, to 3.03m at fastest pace, an increase of 71%. Thus, although the absolute number of steps that I take per 100m declines as I run faster, but my speed overall increases because my cadence increases by about 13%, my stride length increases by 71%. These numbers show that upping both cadence and stride length are critical for me to increase speed, but stride length appears to be the bigger contributor. This is what I expected, as my sense is that I tend to modulate stride length moreso than my cadence in order to control my speed – my cadence stays fairly steady on most runs over a range of easy paces (for example, below is a plot from a very easy trail run I did yesterday showing cadence in green and pace in blue – click for a larger view).
What I also find interesting is the comparison of my numbers to those posted by Alex Hutchinson. For a given speed, my cadence is considerably higher than Alex’s, but my stride length is shorter – another great example about how individuals can take different approaches to accomplishing the same result (in this case, speed). Alex is a much faster runner than I am (he’s a former elite), and I also suspect a lot lighter, so I’m curious how those factors might play a role. I’m also curious whether my own data might be influenced by shoe weight – I ran today in a very lightweight shoe, and I’m tempted to try the same with something double or triple the weight just for kicks and see if the results vary.
I think perhaps the biggest take home message here is that stride rate can and does vary considerably with speed, and also between individuals. The 180 number gets thrown around a lot, but I see no reason why this number need be the gold standard that everyone should shoot for. For me, it’s actually a bit lower than my “easy pace” cadence, and for Alex it’s quite a bit higher. I prefer the 5-10% rule myself – if you are an overstrider, consider upping your cadence by 5% from your easy pace baseline, and realize that that number will change with speed. If you need a bit more, consider 10%. But, like so many aspects of running form, we have little concrete and direct data that changing cadence will prevent injuries. Indirect evidence on joint loading reduction are tantalizing, and anecdotal evidence abounds, but realize that much work remains to be done before any firm conclusions on cost vs. benefit of cadence change can be made.
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About Peter Larson
Would you be so kind as to provide the raw data as either CSV, XLS, or XLSX files for analysis? I’d like to crunch the numbers myself? If so, please reply to ef.romero@gmail.com. Of course if I find anything of interest I’ll share my findings.
Just posted as a Google spreadsheet here: https://docs.google.com/spread…. You should be able to cut and paste this into excel without messing with the formatting.
There appears to be some interesting non-linearity in the data, which makes me curious to try to extend the speed a bit at both ends and fill out the faster end with some more points. Will make for a difficult workout!
Let me know what you come up with, or if I made any errors (quite possible!).
Pete
Amazing how that little curve seems to pop up everywhere in nature . . .
Oh and BTW, thanks for posting all of that great data AFTER I turned in my project for simulations and modelling was due. that would have been more interesting to pick apart than Afghanistan data :)
Interesting analysis. Tough to come up with an absolute rule that is also useful, but it does seem that for most runners, a cadence under 180 suggests that something could be improved. Would you agree?
There’s increasing anecdotal evidence that the presence of any footwear, however light, fundamentally alters stride mechanics. So it would be interesting to see these graphs for a runner in his “natural” state, i.e. barefoot.
Interesting Pete, do you have heart rate info to compare to cadence/stride length?
Lee Saxby mentions that a cadence of 180 taps into the body’s natural frequency of muscle oscillation (when running ‘barefoot’). I would use this as a starting point but as you’ve found, cadence will vary with speed so it’s up to the athlete to find their ‘natural’ cadence.
Thanks for your little experiment!
Speed equals stride length times cadence. Just the thought of your speed, from a jog to a sprint, being influenced only by stride length was so confusing – highly unlikely.
Thanks, Pete!
Yes, both are important. What would be interesting is to see over a range of people how much they relatively rely on one vs. the other.
the only people saying speed is only influenced by stride length are the ones who then go and do little experiments to debunk the theory. No coaches have actually said that speed is only influenced by stride length.
http://en.wikipedia.org/wiki/S…
I’m not trying to debunk any theory that only cadence is important, and I’m not talking about coaches. I’m talking about the notion that seems to be around a lot of places on-line that 180 is a magic number. Not everyone who reads this blog is a running coach, in fact I’d venture to guess that the vast majority are not. No need to get all worked up.
When coaches talk about 180, they are talking about finding a range that the runner can actually sustain for a distance run.
You ran at speeds much, much faster than your 5k pr. An entire minute per mile faster. In other words, you increased your speed and your cadence went up.
I don’t think I’ve ever seen a running coach say that changing stride length is the only way to run faster, just that once you get up around 180, any increase to that cadence will start moving you closer and closer towards a sprint. Hence, the suggestion for DISTANCE RUNS is to keep the cadence AROUND 180 and increase stride length. The body loves rhythm.
Every coach I’ve seen talk about the 180 cadence fully agrees that when sprinting the cadence will go way up. Again, this is not sustainable on a distance run. The coaches will usually say something along the lines of “speed is a result of stride length x stride rate” both have an effect on speed. We recommend first working on getting your cadence up to around 180 and then work on lengthening your stride out behind.
Again…this is for DISTANCE RUNNING NOT SPRINTING.
I’ll add that my cadence at my 5K pace is well over 190 steps per minute, which is not sprinting, and is about 10 steps/min higher than my cadence at easy pace.
Pete, is there any evidence that would show leg length has anything to do with all of this? It would seem to me that those like myself with shorter legs will have a shorter stride AND a faster turn over rate. I know for myself, 180 seems slow and sluggish. My typical pace is closer to 190, and 5k pace is about 195. Just wondering if leg length has anything to do with the overall equation here.
I’d like to second this. I’ve often thought about the whole “180” theory and thought to myself that if we all ran at this rate then you would think a taller runner would cover more distance during that time… so someone short like me would have to just increase the rate. I know for a fact that when I run casually with my 6’3″ friend, I feel as though I take 2 steps to his one to keep up.
I’ve been focusing on optimal cadence a bit lately; especially with my Newtons because I’m trying to get the most I can from the action-reaction technology. I’m beginning to sense an optimal cadence where I get the most return from my shoe. Here are my interesting thoughts. I think that optimal/efficient cadence is more related to elastic recoil concept (and ‘around’ 180 often fits with a lot of people at a moderate running pace). I think the length-tension relationship of our muscles/tendons has a lot to do with this optimal frequency. So everyone’s optimal cadence will be slightly different as we all have different length-tension relationships in a muscle/tendons. So as you start to increase speed, you begin to increase your cadence because you cannot create the same percentage of elastic recoil energy with the now lengthened stride length (which is leading you outside of you optimal length-tension range to create elastic energy). So your stride now quickens and a higher percentage of you energy is now coming from active muscle contractions. But what if you could develop a length-tension relationship in your muscles/tendons that stored elastic energy more efficiently at a longer stride length….ahhh, you’d be running at a faster speed while still maintaining that cadence where you store optimal elastic energy. Run faster using less active energy? If you train entirely under your aerobic threshold, you notice that over time you become much faster while maintaining this same low heart rate. Soooo, if you stretch your muscle-tendon units over time, in correlation with your increased aerobic function, then you should be able to run faster and faster while maintaining your ‘individual’ optimal cadence at creating and releasing elastic energy. Makes sense in theory, haha. But then you won’t be able to run slow anymore because you can’t store elastic energy efficiently at this speed.
It’d be interesting to see information about impact force as your speed and stride length increase. It seems that increasing stride length would require a more poweful push off and that this increased power would translate to increased impact force and strain on the achilies/calf muscles… of course I could be entirely wrong, it’s happened once or twice!
I wish I had the equipment to do that! Maybe someday…
No Doubt! if only we run nerds had every imaginable tool at our disposal!
I find this interesting because when I read about barefoot running, the general guideline seems to be that you don’t to push off so much as lift your leg off the ground and use a forard lean at the hips to keep you moving forward. Using this technique with increasingly longer strides seems challenging to say the least.
I’ve often wondered if the height of a person might also be a variable to consider when thinking about good cadence. Thanks Peter!
Hi, I discovered this blog a little while ago and now the time is near for my first comment :-) Is anyone of you familiar with this tool: http://www.natural-running.com… It calculates the optimal stride frequency, taking into account your length, BMI and pace. Unfortunately for most of you (I guess) it is in German…
I was pleased to find out that I had the ‘right’ frequency, running at 15 km/h in my hattori’s. However, I haven’t measured my frequency at other velocities. I don’t know what the result would be, since I feel that I tend to adapt stride length more than cadence when varying speed. Of course, ‘feeling’ doesn’t say anything, measuring does. However, I noticed that in general my cadence has gone up a little since transitioning to more and more minimalistic shoes and adopting a more mid/forefoot landing. And that simply feels good :-)(Apologies for any sloppiness in my English writing, since English is not my native language.)
Thanks for sharing, need to convert my measurements to metric and give it a try!
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Pete:
When I lecture on barefoot vs shod running biomechanics, I make the point that the increase in stride length with increasing running speed combined with the fact that barefoot running causes a shortened stride length vs shod running, may be one of the main reasons why we don’t see hardly any elite runners running barefoot in races: because running barefoot limits the stride length of most runners on hard surfaces, thus limiting racing speeds.
That might be an interesting subject for one of your next discussions.
Cheers,
Kevin
I had thought about this – I’m devising a way to attach my sensor to my bare foot. Tape may be the best option, which would be painful for my hairy hobbit feet. I can run 5K pace barefoot without too much trouble, but not sure about sub 5:00.
Pete
Check out what Patrick Sweeney did barefoot. 4:42 mile with out any sort of preparation. http://bourbonfeet.blogspot.co…
I couldn’t run a 4:42 mile no matter what I had on my feet! Unfortunately, my ability to self-experiment has some limits :)
I hear you but It does show that it is possible to run fast barefoot.
I’d never dispute that point. Most people don’t run barefoot, but there certainly have been some very fast barefoot runners. On the right surface, I can probably run just as fast barefoot as I can shod.
I knew you wouldn’t. I guess I should have replied to Dr. Kirby’s comment above.
Theo:
I ran plenty fast while barefoot, while in college, doing mile interval training on a grassy baseball field. Collegiate and elite athletes have been using barefoot running training for at least the last 50 years as an adjunct to their weekly training runs. Barefoot running, contrary to the barefoot running propaganda from Born to Run, has been used by competetive runners for decades.
However, almost none of the elites race while barefoot. Why is that?? Is it because of the monetary incentive of shoe contracts, is it because of perceived injury risk, or is it because they can actually race faster in lightweight racing shoes/spikes than they could while barefoot?
Can you name one athlete that has set any world record in any track and field event or any road race while running barefoot within the last 20 years?
Can you name one runner that has won an international level marathon while barefoot in the past 50 years (BTW: Abebe Bikila’s 1960 marathon in Rome was over 50 years ago)?
Cheers,
Kevin
Just because they don’t doesn’t mean they can’t. I’m so tired of the argument of “well the elites do this or don’t do this”. I would bet with the right surface and preperation. Fast times could happen with elites running barefoot.
Why would an elite runner who depends on not getting hurt to continue to earn a paycheck race barefoot if there is a risk of stepping on something or getting spiked? I think the speed issue is irrelevant – when you are running as fast as those guys do the risk of injury is a lot higher, and you stand to lose a lot if you can’t run because you puncture you foot. Shoes allow you to focus on the race, and not where your next step is going to go.
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Disagree…You naturally shorten your stride while running barefoot or in minimalist shoes as an innate mechanism to bring your foot landing position closer to your center of mass, thus reducing impact force and loading rates, and bringing your cadence closer to a more efficient elastic recoil frequency (Some good studies on this; AND it just makes sense). When you run at faster speeds, you do need to lengthen your stride (especially if cadence stays roughly unchanged), but efficient running mechanics will increase the forward lean of your body, thus moving your center of mass more forward, and still allow you to foot strike near your center of mass with this lengthened stride. Barefoot running does nothing to ‘limit’ your stride length, except maybe cause you to lose a bit of that ‘good recklessness’ in your running gait which a shoe allows
It’s also worth noting that research has shown that at least in sprinting, some individuals are stride length regulators, whereas others are stride rate regulators. There are different ways to achieve top speed.
From Salo et al., 2011: http://journals.lww.com/acsm-m…
“Previous studies have generally identified only one of these variables to be the main reason for faster running velocities. However, this study showed that there is a large variation of performance patterns among the elite athletes and, overall, SF or SL reliance is a highly individual occurrence. It is proposed that athletes should take this reliance into account in their training, with SF-reliant athletes needing to keep their neural system ready for fast leg turnover and SL-reliant athletes requiring more concentration on maintaining strength levels.”
I def agree with this. That’s why I think it’s necessary to distinguish between a ‘running fast gait’ VS a ‘sprinting gait’. but even in ‘fast running’ it makes sense that you reach a point with your increased stride length that leads to your elastic recoil system working less efficiently. Therefore cadence must increase to bring the length-tension relationship of your muscle/tendon units back to a more optimal range. I like to think like Dr. Cucuzzella — just go out there and try it, and see what makes sense. You have to find that sweet spot between cadence and stride length, and that sweet spot varies at different speeds
I would add one thing to the statement that “that sweet spot varies at different speeds.” It will also probably vary in different people.
Exactly — And I even think that the type of shoe will influence that individual ‘sweet spot’. Though the more shoe you have on your foot, the less sweet that spot is going to feel
Great post Pete, the stride length increase as the pace increases is exactly what I’ve seen during my own speed work, especially at the fast end of things.
Interesting post Pete. I need to read it more closely, but I have had similar general thoughts and experiences regarding the “need” to hit a particular cadence to accomplish whatever. Have you plotted your HR vs cadence ? My anecdotal (i.e. have not done the analysis myself) casual observations of my HR vs cadence vs pace show a pretty strong relationship (holding course and conditions constant). If I am trying to keep effort (and the only numerical measure I have is HR from my Garmin) below some level (Maffetonesque training), I also have to keep cadence from speeding up.
bob
Have not tried this, but it would be easy enough to do. I’ll give it a shot and see what happens.
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Brad:
Do you have any research to back up your claim that “You naturally shorten your stride while running barefoot or in minimalist shoes as an innate mechanism to bring your foot landing position closer to your center of mass, thus reducing impact force and loading rates, and bringing your cadence closer to a more efficient elastic recoil frequency”.
Here are six scientific studies that showed an increased impact loading rate in barefoot running versus shod running:
Dickinson JA, Cook SD, Leinhardt TM: The measurement of shock waves following heel strike while running. J Biomech, 18:415-422, 1985.
De Koning J, Nigg B: Kinematic factors affecting initial peak vertical ground reaction forces in running. In Abstracts of the XIVth Congress of Internat Symp of Biomech, Paris, France, 1993.
De Clercq D, Aerts P, Kunnen M: The mechanical characteristics of the human heel pad during foot strike in running: an in vivo cineradiographic study. J Biomech, 27:1213-1222, 1994.
Stockton M, Dyson R: A comparison of lower extremity forces, joint angles, and muscle activity during shod and barefoot running. Proc. 16th ISBS, pp. 251-254, 1998.
De Wit B, De Clercq D, Aerts P: Biomechanical analysis of the stance phase during barefoot and shod running. J Biomech, 33:269-278, 2000.
Freedman JA, Dufek JS, Mercer JA: Kinetic characteristics of barefoot running. North Amer. Congress of Biomech, Ann Arbor, MI, August 2008.
And, Brad, how do you measure the efficiency of “elastic recoil” in the human body during running?
Most researchers feel that the reason for the shortened stride length of barefoot running is to avoid heel strike and prevent plantar heel injury. Do you have any evidence otherwise?
Cheers,
Kevin
The titles alone of half of those should throw up a red flag. They mention HEEL striking.
Theo:
How about the four scientific studies I listed that don’t mention “heel” in their title?
Can you name one athlete that has set any world record in any track and field event or any road race while running barefoot within the last 20 years?
Can you name one runner that has won an international level marathon while barefoot in the past 50 years (BTW: Abebe Bikila’s 1960 marathon in Rome was over 50 years ago)?
Cheers,
Kevin
…thanks for the studies. Yes, 2 of them are talking about heel striking while barefoot. That is absolutely not relevant to what I was talking about. A 5 year-old knows you can’t intrinsically modulate forces like that in your bare feet. Another one of your articles actually said that barefoot running produced lower impact GRF compared to shod running (maybe you should read these articles before sending them to me). Another one of those articles basically just said we change our foot landing pattern when running barefoot (did NOT say GRF is higher while barefoot). And I couldn’t get a-hold of the other 2, but judging by the previous 4, it’s not worth my time to find them. Thanks though
I just did a very nice presentation on minimalist footwear within my Physical Therapy department. I’d be happy to send you a copy of my ppt if you are having trouble comprehending these concepts. If you had a stronger grasp on human biomechanics and neurophysiology then you would understand the what I proposed.
Brad:
Sorry if I offended you. I thought we could have a civil discussion. My time is too valuable to be insulted on this forum. I was hoping for a scientific discussion, not to be told that “If you had a stronger grasp on human biomechanics and neurophysiology then you would understand what I proposed.”
Good luck in the future with your career in the health professions.
Cheers,
Kevin
Apologies. Some things you just have to get out there and try, and it eventually makes sense. Jay Dicharry (UVA SPEED and gait lab) has some great stuff out there if you’d like to learn more of the science from someone collecting qualitative data.
And you can qualify elastic recoil by ‘Feel’. You don’t need a study for everything to understand it. You can feel it change at different paces, different stride lengths, different stride frequency, different footwear. It would even feel different if you did some static stretching prior to your run (Which I don’t advise!). Once you find that ‘sweet spot’ you notice that running feels effortless
Kevin, another factor as to why you won’t find a barefoot champion is because SHOE COMPANIES are the lone sponsorship companies for distance and track athletes. Sony doesn’t sponsor Ryan Hall, Asics does.
Conference abstracts are not published papers. As for the others, if you heel strike barefoot, of course impact forces and loading rates go up. There are plenty of studies showing that impact loading rate is lower or equivalent in barefoot running with a forefoot strike compared to a shod heel striker – Lieberman, Divert, Gruber et al., Squadrone and Gallozzi, and several others. Don’t have time right now to dig up the specific citations, but I’m quite sure you know these papers Kevin, and I have written about many of them in previous posts.
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Somewhere in this discussion, two very distinct issues have been conflated: (1) what’s best for pain-free running in a sustainable way for health and long life?, and (2) how can you squeeze out maximal performance for one race?
It’s as true in running as in many areas of life that what produces a “best” performance in the very short term may not be what’s best for the long run.
Following twenty years of running (and too often not running) in constant pain, while I had the the best shoes, inserts, and medical care, I can now crank out a road 20-miler with no preparation and no soreness. Barefoot.
What people are paid to wear to set a world record is of no consequence to me. Why should it be?
I agree completely. I’m far more interested in what allows runners to enjoy the sport without pain than I am in the maximal performance question. I’m not a coach, so I’ll leave that to them, and elites are running at the very edge when it comes to injury risk so their considerations are completely different than 99% of the runners out there.
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Here’s an idea for an
analysis post: Ibrahim Jeilan. What is this guy doing over the last 100 meters
when he’s taking down Mo Farah? (Who himself at that point is running just as
fast as Kenenisa Bekele and Haile Gebreselassie did on final laps in their
primes). There’s something more than the obvious difference in speed to Farah’s
about Jelian’s running technique over the home stretch that sticks to the eye,
but I can’t pin down what it is (again, except for speed). Stride length?
Cadence? Hip and knee angling? The guy powers over the line almost as if he was
Usain Bolt – what is going on there?
Already did it :) https://runblogger.com/2011…
Jeilan ups his cadence dramatically in the final 100, Farah holds his constant. Did not calculate stride length though.
Pete
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Perhaps I’m an outlier, but as a very “challenged” runner (missing L5-S1 disc, very flat feet, slightly bowed legs, lifetime asthma) I’ve had to put in lots of work on my stride.
I’ve spent the last three years experimenting on myself to find a stride with the least impact (because of the missing disc) that is also efficient (max speed given my bad lungs). I do all my runs (race & training) wearing a Garmin Forerunner 305 with the shoe pod, and I also do all of my training runs with a Seiko DM-50 metronome.
I’ll leave out the boring experimental process, but my result has been that to have a smooth, fast gait during races (at whatever cadence feels ‘natural’), I must consistently train at a minimum turnover rate of 190 bpm (faster for sprints and downhill).
My theory is that it is MUCH harder to learn a high cadence while maintaining good form than it is to lengthen the stride. So (for my sample population of one), no matter the speed, training at a high cadence has benefits.
I would agree – consciously altering cadence can be really difficult without altering the stimulus underfoot. I’d love to see a study that looks at whether cadence changes as one adapts to different types of shoes.
Pete, I’ve been hoping you’d to work up a cadence post. Thanks.
I can’t show a study on the effect of shoes on cadence; just my own experience. I believe in the 3-steps/sec (180/min) and see 2 key motivators to reach it. One is avoiding foot, knee and other pain/discomfort and the other is power efficiency.
Yep, cadence can adapt to shoes. When I methodically, 10-20% per week, transitioned this past winter from typically overbuilt/squishy 12mm drop NB’s to MR10s, my cadence did change to around 3, as intended by NB. Why? If you don’t change to ~3,you suffer the painful consequences. The aversion to pain in turn encourages a mid-foot strike (the shoe is padded a bit in the arch). This is like a musical instrument that can only be played one way. Play it right, you’ll make beautiful music. Play it wrong? Ugh J. Finding that physical and mental sweet spot is tricky; even the initial training expends additional energy. I’ve used some tricks, like imagining I only have the pad behind the foot ball to land on or running like I did as a barefoot kid on hot asphalt!
On the power efficiency of proper cadence, think of your legs as an electric generator, a pump that propels your body forward. The goal is the most efficient power generation via that pumping action. My day job is an IT network engineer and deal with data center power requirements a bit, so time to geek out. I’m fascinated by the analogous efficiency between cadence and 3-phase power systems. Ah, yes, the power of 3 again! In 3-phase power systems, alternating currents are carried in 3 120-degree offset voltages. This creates a more constant voltage, a more efficient pumping action and the most available power. Next time you run, notice how much power you expend in longer strides and varying slower cadence. Then, do the same during 3
steps/sec. I myself notice a dramatic difference. Find that sweet spot. Then, see how you can increase speed while maintaining that 3 steps/sec.
Now…let’s get your Physics Department colleagues to find the human body’s most efficient pumping speed. Regards!
I agree: Modifying my turnover/cadence *was* difficult! Seldom are “easy” changes able to cope with complex problems. For me, once my legs got used to turning over faster at all speeds, my ability to sprint improved, as did my downhill performance.
However, for me, an increased cadence made my shoe choice matter *less*. When I keep my cadence high, I feel more like I’m floating over the road, rather than trying to pound it into submission. Shoes matter much more when you’re pounding!
Downhill is often an issue for runners who otherwise have no significant gait issues. Being able to wind the cadence way up greatly reduces downhill stresses (especially the tendency to jam the toe into the front of the shoe).
For minimal stress, the high downhill cadence should be combined with a short stride length. This is surprisingly difficult to accomplish unless you consciously train at it. In environments other than downhill.
I was messing around. Bit with my cadence on my run today – tried to hold speed constant and run with a faster or slower than normal cadence, and it just felt wrong. At my typical pace, my cadence seems to almost be invariant from the 180-184 range.
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Wow, lots of comments on these last two posts – Pete shows that you are hitting the mark on what’s of interest to runners, or least the more geeky ones!
A couple of thoughts that hopefully won’t overlap too much with what others have added to your posts. First up, it’s great to see an illustration that cadence isn’t invariant with speed. The idea that 180 is an ideal cadence has always struck me as odd and unhelpful. Hopefully NewBalance and other protagonists of the 180 cadence will read your blog and others that have highlighted how 180 isn’t even right for one person, let alone everyone of all heights.
Next thought is that the energy cost of running faster is higher so you’ll need to pull in be oxygen and pump out more carbon dioxide, this all means you’ll need to breath are greater volume of air, so either breath more deeply or breath more quickly, or more likely both just like cadence and stride length ;-)
Whether the need to breath faster has any influence over the cadence we choose as we go faster I couldn’t say. For sprinting I would have though there would be little need for influence, but for distance running I could see how getting enough volume of air through would influence cadence. I have no clue whether this is the case, perhaps others will know.
My next thought is our gait changes as we go from a jog to a sprint. For most runners our foot strike changes, from heel strike/mid-foot to forefoot strike, this may have an influence on cadence as we get more from the elastic recoil of our feet/lower legs. Also, or likely much more significant, is that as we get faster our feet naturally kick up towards up butts much more when running faster which reduces the moment of inertia of the leg making it easier to pull forward? However, this wouldn’t be quite as clean cut though as we also have far more range of motion when running fast so our limbs have further to rotate to get from the further back to further forward position. How might this all come out in the end – Is it easier to run at high cadence when running fast simply due to changes in gait? Can’t answer this one either, but an interesting question to pose no less :-)
Finally what is the role of how fast we can generate the forces required as we get faster. The average vertical forces are constant no matter what speed we run at – gravity doesn’t change, but typically one would expect the time on stance to shrink as we get faster so we have less and less time to generate the forces, so the peak forces have to go up. If we are able to up our cadence by reducing time in the air then the peak forces we generate won’t have to go up so rapidly, in fact if we can keep the ratio of time on stance to time in the air then the peak forces will actually be the same. Given that their isn’t a trivial metabolic cost to upping cadence it’s not suprising to see that runners will naturally be increasing cadence and peak forces to run faster.
Oh… on a non running subject, but on cadence, today when out on my bike I caught up with a cyclist, he was dawdling along the trail, while I was cycling about faster, but still as a easy pace for me. I checked our respective cadence and mine was over twice as fast, he looked like he was peddling a bit slowly but nothing out of ordinary, and I didn’t feel like I was peddling fast – it just felt natural and easy. The more time I’ve spent on my bike the more a quick cadence has become second nature, I suspect I’m changing up later, and changing down quicker than I used to just to keep the cadence up to a comfortable level.
On a totally different topic, while out on my ride I was my first complete white Highland Cow, only ever seen ginger and black ones before so it’s quite a novelty.
Thanks for chiming in as always Robert! I can’t keep up with all of the commentary on the last two posts!
I do have a large dataset of stance and flight time for marathoners at two points in a race. If I ever have time to finish the video analysis, I hope to get it published and it may touch on some of the issues you have brought up.
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Hi Pete,
Is there any chance you could send me the stance and flight time data?
A couple of weeks back I started putting together mathematical model of the relationship between time on stance, time of flight to maximum G loading and vertical travel on stance and in the air. The vertical travel and time on stance relate to the joint angles which in turn relate to the moments that our joints and the muscles and tendons need to handle. Some of the maths is straight forward enough to analysis and draw conclusions by hand, but some of the maths was getting a bit too complicated for me draw any definitive conclusions from – these I’ll need to put into a computer and get it to plot the relationships. My motivation behind the math models was to explore the question about a runners height and cadence, to tease out what the equivalence might be.
The data you have would be very useful to plug in into the models, ideally we’d want height data for the individuals as well, but we can still can do useful analysis without this.
I was blown away by this post and especially by the dialogue between all the poeple intrested in this subject. I have no knowledge on this topic. However I grew up on a remote island and never wore shoes until I was 13 years old. During all this time we ran on unsealed roads, on the coastal rocks etc. We never had any injuries, infact our feet were healthy and strong so I think, (no graphs or tests) that feet can be just as effective as running shoes. I do agree that athletes would miss out on sponsership if they did not wear shoes.
Personaly what would you say be the best hiegth to strde length ratio
There likely is no universal “best,” depends on the individual.
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This is unbelievable. Such detail and rigor!
If you wan to improve your running cadence, you should try Runnahoo – Running metronome for Android! It’s free! http://goo.gl/1VvPI2
A very compelling article. I now feel reassured about my cadence getting up to 189 during intervals at 3m30s/km pace whereas for the rest of the week, at slower paces of 4m30s to 5m00/km my cadence is at around 181-183. Until I read your article I had thought my interval pace cadence was too high. Thanks!
Nope, perfectly normal. My cadence regularly goes over 200 on fast intervals, and may drop below 170 when I run with my beginner 5K group at 10:30-11:30 min/mile pace.
Thanks Peter, interesting article.
I’ve been struggling to answer a question from someone I coach:
I’m 5 ft 3, he’s 6 ft 4 (over a foot taller!) If we run at the same pace does he take shorter strides, less strides or a combination of both? (I don’t have access to a treadmill etc to work it out)
That then leads to the question “does a short athlete need to work harder than a tall athlete to cover the same distance in the same time?” The stature of elite endurance athletes suggests otherwise.
Be grateful to hear your thoughts.
Great question. The easy way to figure it out would be to simply count the number of steps you each take in 30 seconds and double it to get your cadence (steps/min). If your cadence is the same, then stride length would need to be the same, but stride length relative to leg length would likely differ and thus your form might be a bit different. Tough to wrap my head around, would be interesting to know the cadence numbers!
Thanks for the reply.
Yes were doing the count as you run technique and he did seem to be taking fewer strides although it wasn’t a particularly accurate test.
I might try to do some more testing to get a better idea.
You could also try an app like iSmoothRun which will show cadence in real time. The Garmin 620 will also do cadence and estimate stride length with the HRM-Monitor.
Thanks.
An increase from 1.77m to 3.03m is an increase of 71%, not 42%. You may need to qc your math and spreadsheet.
You are correct, rusty math skills…can’t believe nobody else caught that!
It (the increase in percentage stride length)helps make your observational point stronger. Speed is an increase of both cadence and stride length. For your data, stride length is more significant.
I need to increase both…
Great discussion and very helpful all around.
I realize this thread goes back a ways, but I thought I’d add a different perspective. I’m new to running as part of transitioning to triathlon from competitive bike racing.
When I started last year my form was typical new runner. Cadence about 150 to 160, over striding and plenty of bounce. And my running times, although not terrible, were middle of the pack and nowhere near in line with my cycling results. So I decided to look into form and quickly came across the subject of cadence and that it was probably more efficient to get that up above 180.
The thing I wanted to mention is that in studies from cycling they found that a cadence above 90 rpm is better, but not because it is metabolically more efficient. It is better because it favors the bodies aerobic system more than its relatively limited anaerobic systems. Bike races are typically 2 to 4 hours long, so that’s a big deal. A well trained aerobic system can use fat stores almost limitlessly, rather than the limited supply of cellular glycogen, which is the fuel for the anaerobic system.
Put simply if you take away all resistance, and turn over the pedals of a bike 50 times a minute, that is going to require less metabolic output than turning over the pedals 90+ times a minute. Once you add load, however, the benefit is that the absolute force per revolution required to move the rider and bike forward is less at the higher rpm. And since it is less at the higher rpm, the aerobic system can carry more of the load.
In competitive cycling it is common to use a watt meter in the crank to measure absolute work output, along with HR and cadence. It is simple to see this principle in action by riding the same patch of road, at the same watt output at 50 rpm, and then again at 90 rpm.
At the lower rpm it is much harder to turn the pedals over, even though the work output (and speed) is exactly the same.
Foot strike characteristics notwithstanding, this leads me to believe that similar principles may be at play in running, that a higher turnover likely allows the aerobic system to take more of the workload.
For me personally, I’ve taken this to mean 180 isn’t some magic number, but more that quicker turnover (generally above 180) is likely better because it is less work per step for the same speed. Granted on a bike, its a simple matter to change gears and keep cadence the same. It’s been a learning process to vary my stride length in order to keep cadence high at lower speeds.
At any rate, just another perspective. Thanks again for the interesting discussion.