A few months back I wrote a post on a study that found that rotating running shoes can reduce injury risk for runners. The logic is that shoes of different construction alter how forces are applied to the body, and that by rotating among a few different types of shoe we mix up the way the body is stressed on each run (particularly for those who run mostly on uniform surfaces like asphalt roads). If we avoid stressing the body the same way every time we head out the door, we reduce the risk of a repetitive stress injury to a given tissue. Seems logical, and it’s a practice that I both advocate and employ myself.
A new study by a group of researchers from Luxembourg seems to lend additional support to this idea. On his blog, Running Research Junkie, Craig Payne summarizes the research by saying:
“This was a prospective cohort study in which the runners that were recruited recorded training related data. They compared the training data between the group that got an injury and the group that did not.
What they found was:
- those that ran more than 2hrs a week were at a lower risk for injury
- parallel use of more than one pair of running shoes was protective
- the week-to-week absolute change in distance was protective
- a previous injury was a risk factor (which pretty much every study has also shown)
I don’t have much of a critique of the study as what we know is just based on the abstract above, but nothing jumps out at me at this stage as being an issue.”
So those who used more than one pair of running shoes regularly in training had a reduced risk of injury. Since it’s only an abstract from a conference it’s unclear if this could be two different pairs of the same shoe, or if they had to be two different shoes, but the results suggest benefit to not doing every single run in the same pair of shoes.
Head over to Running Resarch Junkie to read the abstract and for additional commentary.
You might also like:
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On Overpronation and Neutral Running Shoes: Guest Post by Anders Torger
Heel-Toe Drop or Offset: What Does it Mean in a Running Shoe?
Newton Running: Q&A With Ian Adamson, Newton’s Director of Product Development
Form Differences Among Barefoot Running, Minimalist Shoe Running, and Standard Shoe Running
About Peter Larson
Interesting.
One thing that’s got me wondering, though, is if there might be some socioeconomic “protective factors” explicitly at play here as well. That is, a recreational runner who can afford to splurge (relatively speaking) on running shoes might also have access to better advice/training, better nutrition, more time to run (which the study has, found to be a protective factor in itself), etc.
Zed- I reckon there’s some possible socioeconomic factors at work, but don’t really see how having multiple pairs of running shoes costs any more (for example, having 2 pairs of shoes that you rotate evenly over 800 miles costs the same as getting 1 pair every 400 miles). This was mentioned several times in responses to Pete’s original post on rotating shoes. Plus, it doesn’t cost much to get pretty solid training advice (such as this fine blog here!).
That said, there might be other similar factors at work, as you’ve mentioned. My concern would be with regard to the independence of their variables – i.e., I imagine that runners who spend more time running are also likely to have multiple pairs of shoes. So do they have lower injury risk because they run more frequently, or because they rotate shoes? Or is it because of something else related to these factors (e.g., maybe more frequent/experienced runners have a better sense of when to back off at the first sign of injury)? Anyhow, interesting topic, and I look forward to a little more research in this vein.
I think Trail Running Dad is on to something here. It makes sense that runners who own more shoes probably are also more experienced, know more about good form, know when to rest, etc. Maybe owning multiple pairs is indicative of the kind of obsession and attention to detail it takes for some to be successful and injury-free runners.
@Trail Running Dad: Oh, I definitely agree that buying multiple pairs of shoes at once and rotating them or buying them sequentially as they get worn out shouldn’t be all that different in total cost over time (I think I made a similar comment in one of Pete’s older posts).
That said, I do think that a recreational runner who is willing to spend more in one go for running shoes might be willing to spend more for other things like better coaching (or any coaching, for that matter) or nutrition. Poor use of words on my part in my previous post, though, as it seems like I’m suggesting that pure socioeconomic variables can serve as protective factors… I guess it isn’t so much a matter of a recreational runner’s disposable income as it is a matter of how important running is to the recreational runner and how knowledgable the runner is about the preventative health/safe training aspect of it.
What we need is a prospective study comparing a group given one shoe to train in for say 12 weeks, and another group given 2-3 pairs to rotate. That should help sort this out.
And then a large enough sample size to see meaningful differences in injury rates… which means dishing out quite a lot of shoes!
Yes, but if a shoe company was confident enough that rotating would reduce injury risk, and that meant ultimately that there was strong evidence for people to buy multiple pairs, I could see one donating shoes for such a study. Of course then the study would be criticized for bias since it was supported by a shoe company :)
I see rotating shoes as beneficial for some or even many runners, but it can be entirely a non-issue for runners with a no-injury running history. Those who don’t need a rotation know who they are.
One possible reason for injury benefits of rotating shoe models might be that a runner doesn’t necessarily know if a shoe might be contributing to an injury. Using multiple pairs cuts down on the usage of a shoe that potentially contributes to an injury.
I was basically injury free for 20+ years (until trying minimalist shoes), and for most of that time, I would use one pair at a time. Like some other dude in the forums a couple of weeks ago, a good shoe would last thousands of miles until it totally disintegrated. With a bad shoe, I might have made 10-300 miles before I would notice it causing pain in my knees. This would go away immediately switching to a good shoe.
I do have many pairs of shoes, but it’s not for injury prevention. It’s more for having specific shoes for different traction needs, faster running/racing, waterproof/snow use, or just having a dry pair to use when a favorite is soaked. Saying that having a rotation helps prevent injury is mostly justification for being a shoe geek :), at least for those who know it doesn’t matter for themselves.
But do you vary workouts, run on trails, etc.? If so, running in one shoe may not be an issue since there are other sources of variation in your training. I think the max benefit of a rotation is for the person who does mostly the same type of run on the same type of surface every time they go out (like my wife).
Sometimes I varied some of those things, but sometimes I didn’t vary things much for years. I run on trails often, but I also did up to 5,000 mile years where maybe 2/3rds was on pavement. I don’t think trails are necessarily protective. I love them, but things like sprains, scrapes, falling injuries, etc are more likely on trails/mountains.
The (lack of) injury history is a stronger effect than multiple shoes, so that’s what I’m seeing for myself.
For your wife, is a rotation better than using her Hoka full time?
She’s been alternating the Hokas and Altra Torin for about 9 months and hasn’t had any injuries that have stopped her, and this is after several years of nagging problems. But, it could just as easily be that we’ve found good matches for her rather than the rotation being a benefit. She really doesn’t run a lot of miles, but is very prone to injury. I’m more like you, could probably run all of my miles in one shoe without issue, but I’d get bored :)
Pete-
To your knowledge, has there ever been a study that looks at how long it takes foam to rebound/recover after each run? We’ve talked about this a lot at our lab but have never seen any definitive research…
If you are asking if resting a shoe makes a difference in cushioning, it doesn’t. A study isn’t needed, just a knowledge about materials or a little experimentation. Shoes effectively rebound right away after each step. Looking at how much you can compress an EVA midsole with just your fingers, I estimate that you would compress a 20 mm sole on the order of 5 mm to 15 mm (don’t have to be accurate) with each step. If it remained flattened anywhere near that amount after a step or at the end of a run, it would be easily measureable. But with calipers or even a crude tool like a meter stick, you’ll find that 20 mm stack height will still be 20 mm after a run. For the sake of argument, consider what would happen even if a sole takes more time to recover. Say it measures 19 mm after a run, and rebounded to 20 mm after two days. Would you notice the difference after the first step of the run two days later? You are immediately compressing it many times that theoretical 1 mm amount with the very first step.
There is measurable long term compression on EVA midsole with use that doesn’t rebound. My current shoe started out at 30 mm stack height in the heel. It now measures 25 mm after 1,100 miles.
I’d agree here. My understanding is that EVA foam is composed of little sealed bubbles of air. I might be wrong, but for rebound to occur the bubbles would have to be porous. Like a sponge sucking water back up after compressing. If they were porous the cushioning would be lousy, as running with a sponge attached to your feet would feel. Compression sets over time take place because the bubbles burst and air escapes, and they don’t refill. Here’s a good article on this: http://anathletesbody.com/2011/05/16/do-shoes-have-feelings/
And, what does it mean by week-to-week absolute change in running distance? Does that mean runs of 3, 4, 5 one week and 7, 2, 3 the next? Seems like that also adds another injury prevention variable.
I agree with Pete’s suggestion for the 12 week study. We need to limit some variables.
so what about being barefoot?
I almost run exclusively barefoot, depending on the weather, or place i run (if there’s a ton of goat heads lol)
i’d assume it’d be just as good as multiple pairs of shoes considering the completely unrestricted movement of foot…and different surfaces
Pete:
The idea of buying multiple running shoes and rotating them is not a new idea. I believe I read about this idea of rotating training flats in Runner’s World magazine back in the late 1970’s when I was running for the cross-country and track teams for the UC Davis Aggies. Also, during my years of running and racing during the late ’70s, most of my Aggie teammates also had a few different shoes to train in.
Anecdotally, I seemed to have decreased aches and pains and fewer injuries when I ran in at least two different running shoes. When I was doing marathon training, generally about 80-85 miles a week, I liked having three pairs of shoes due to the increased mileage. When I was only training 60-70 miles per week, I seemed to do fine with only two pairs of shoes. Sometimes I would run in my orthotics in one pair of shoes, but not in the other. My UCD coach (W.C. Adams, a PhD in exercise physiology) felt that having a variety of training stresses was important in keeping his runners less injured. From my experience, I agreed with him.
At that time from over 35 years ago, the thought among many of us that were rotating running shoes was that by running in a different running shoes during training that your legs and feet would receive different stresses on different specific body parts with each different shoe so that the chance of “overuse injury” on one single body part would be lessened. With that in mind, I would never get two pairs of the same shoes to train in but would rather try to find two shoes that I was comfortable in but had slightly different midsole/outersole construction designs.
In addition, during those days when I was often training 70-85 miles per week and doing both AM and PM workouts (double workouts), it was nice to have one shoe drying out while I went for my second run of the day in another shoe. Of course, in wet weather or soggy fields, having an extra pair of shoes meant that I could generally have a dry shoe to put on for my next run.
Having been a runner for over four decades, and seeing fads and trends come and go within the running community, it is somewhat amusing to me to see that some of the things that we did and thought back in the early years of the “Running Boom” are now being talked about again as if this was new or recently discovered information.
First it was the “discovery” of “minimalist shoes”, even though we ran in racing flats that were of nearly identical shoe construction 40 years ago. Secondly it was the “discovery” of taking shorter strides to improve running form, even though my high school cross-country and track coach in Sacramento from 1972-1975 continually told his running athletes to shorten their stride to increase their running efficiency. Now it is the “discovery” that running in more than one shoe can produce fewer injuries, even though this was fairly common practice in intercollegiate athletes from over 35 years ago for the same reasons.
I wonder what will be the next new “discovery”, that running with a combination of increased stride frequency an d increased stride length will make you run faster?
Nothing new under the sun.
Cheers,
Kevin
Very true Kevin, but with new people picking up the sport that weren’t running 30 years ago, old running lore may in fact be entirely new. You can even go back to reading some of Arthur Newton’s stuff from the 1930’s and find him talking about the effect of muscle vibrations, predating Benno Nigg’s science by decades!
This is an interesting dilemna: if one shoe works for you, should you just stick with it, or should you mix it up a bit, to give your feet different kinds of challenges in order to not be too biomechanically dependent on one type of shoe design.
I’m a newer runner (seriously running since last summer), and have found myself in this crux. I started running in Mizuno shoes (first an unidentified model bought in Brasil, then a Waverider 16), and never had any kinds of problem, no pain, discomfort or injury of any type. I did, however, have a durability problem, since I was foolish enough to run on sometimes very rocky trails with the Waverider, which thus got damaged way too early. So a running shoe shop clerk advised me to use an Asics Cumulus 15 and a Fuji Trabucco for trails. I immediately got severe achilles soreness with the Cumulus, and finally achilles tendonitis with the Trabucco. The problem with the Trabucco is clear to me: it’s labeled as “-universal-pronators”, but it includes that much support that they now issued a “neutral” version. But I can’t really figure out what was wrong with the Cumulus.
Anyway, I then bought a new pair of Waverider 17s and the problems immediately disappeared, no soreness whatsoever, and the residual tendinitis in the right foot waned away in a week or two.
So my question is: should I slowly rotate back the Cumulus in my training, to slowly strengthen the muscles/ligaments/tissues that the Waverider apparently had spared (and not to throw out of the window the 120€ the Asics had cost), or just write off the sunken costs and stick to the shoe that works? I’ve recently bought a pair of NB 980 Fresh Foam half price (in Hong Kong), and use them once a week on short easy runs, to get accustomed to a lower drop, and so far the experience has been good.
It’s possible that the Asics just aren’t a good match for you. Maybe a few easy runs and see if any problems arise? But don’t rotate a shoe that gives consistent problems. I have a few shoes that I can tell in a few runs are not going to work for me, and they are ditched from the rotation.
Hey Pete, what about those if us who almost exclusively run in barefoot style shoes? These types of shoes are basically designed to protect the bottoms of our feet and offer little to no support. Since there’s not really any foam cushioning to pad our foot strike or alter our gait does shoe rotating really matter to us? I would think not, curious to hear your response though!
I think mixing up force application can be good for anyone, and if you are in barefoot-style shoes exclusively then running on varied surfaces can accomplish the same result. If you think about how humans evolved, yes we ran barefoot, but we did so on a constantly varying terrain and not on a highly uniform surface like a road. So mixing trails and roads can be a way to approach this without changing shoes.