I honed in on this:

Keep in mind the fulcrum of Hoka;s (heel of shoe to joint center of the ankle) in much longer than a traditional shoe and plays a role here.


I have a funny thing going on in Hoka Clifton. From heel of shoe to mid shoe, there is a slight rocker "up" then from midfoot to toe a "rocker down". I had some weird plantar fascia tightness in both feet that only happened in the Clifton, and I can only seem to link this to the moment arm you refer to. I THINK my brain naturally wants the sole to be totally flat under my heel and not rocking upwards if you can visualize what I mean. I keep trying these shoes and 10k later the same plantar fascia soreness comes back so I just put them away. If you could give me a Clifton with a flat heel, I would be a lot happier. Even if the moment arm is longer than another shoe, it would be what my brain is tuned to when wearing all other footwear or walking barefoot on a floor.

What are your thoughts?

Hey Dev,

I think I get what you mean, but believe it or not a rocker bottom shoe (regardless of type) is designed to "ease" through the transitions from initial contact to foot flat and then from foot flat to toe/push-off. The foot itself will not follow this contour (picturing a shape of a boat hull stretching your planter fascia). In theory a "rocker bottom" shoe would take pressure off the plantar fascia (PF) as there would easier transition to foot flat and less of a requirement on the toes to extend (upward movement) as you transition to push off. Again in theory, the rocker bottom is doing the some work for the foot and I say this outside the context of the shape of the heel of the footwear.

However, in the case of Hoka and other shoes with higher heel heights and/or flares, there is little debate that the moment arms (fulcrums) to the ankle joint are larger. This is in all 3 planes of motion. It is important to understand that these moment arms are not large to begin with, so even small changes can greatly impact external torques and subsequent internal work from muscle, tendon, ligament, fascia...

Example: ~ moment arm for medial/lateral torque at the heel at initial loading (calcaneal inversion/eversion) = 1-2 cm. So a 3mm move (increase) of the application of force results in a 30-60% increase in torque. This is not an extreme example of moment arm increase btw and you can see a significant change in response demand form internal structures.

Of course strike pattern plays a role here as well.

Example: I treated many female HS distance runners for anterior compartment syndrome (essentially an overuse issue with the muscle in the front of the shin that helps to control the foot after heel strike to foot flat). It is a comprehensive approach, but I always looked at shoe type and strike pattern; if they heel strike and have a rear flared or higher heel there is a lot being asked of the anterior compartment muscles. Teach them a midfoot stroke and/or change shoe type with reduced fulcrum and symptoms are reduced (sometimes this is all they needed if caught early).

Back to you and the Hokas; they are likely producing greater torques at the ankle and possibly the forces are being applied at a faster rate also related to the longer fulcrum. The PF is certainly a part of the internal mechanisms that will counter these torques. I also find that Hokas by their design can encourage a heel strike both dimensionally and mechanically (larger heel and the added cushioning makes heel striking more amenable especially on tired legs e.g. I wear them on recovery runs).

There is a ton more to consider, but I would lean towards the fulcrum and strike pattern issue versus the rocker bottom.

What does the wear on your Hokas look like at the heel and how does it compare to your other shoes?

Do you feel your strike pattern is the same?

All things equal; torques will likely be higher.

Not to be misunderstood, I am not a Hoka basher; I wear them and like them. Changes in torque are not necessarily a bad thing and are a part of all footwear and running styles changes. It is important to consider the impact of these change (no pun intended) when it can be implicated to an ailment or injury.

Cheers!

I have ankle problems I.e. Little cartilage left and so every fast or long run I roll the dice on whether I'll be limping for a week.

I got Hoka's and though they are super light and cushy I can't even do short slow runs without a flare up. But my Newtons minimalist don't bother my foot at all.

What up with that?

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�Bloom wherever you are planted"

I with you on this - I have some of the same sensations, and I think some of it comes down to propioceptive feedback - if one gets too much (barefoot on pavement) or not enough (Hokas on grass) feedback, they get out of a certain "bioinformation sweet spot" that allows them to perform at their best.

For me, it's not only a surface issue, but also a transition issue - after getting out of the water, touching ground just feels funny, but then I can get up to speed barefoot on concrete pretty quickly. After getting off the bike, kind of the same thing - it takes a few steps to reacclimate to the sensation of impact. In a grassy transition area, it takes me a few steps longer to get my running legs going after putting on my shoes than it does if the area is a more solid, more predictable surface.

Anyway, more n=1 stuff, but I hear what you're saying.

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Travis Rassat
Vector Cycle Works
Noblesville, IN
BikeFit Instructor | FMS | F.I.S.T. | IBFI
Toughman Triathlon Series Ambassador

One more thing related to "slamming down" in padded shoes. When I first got Hokas I tried doing plyometric exercises that I do for my rehab in them and literally could not without knee pain. In altra instinct or Merrell BareAccess, I would have almost none. I think the brain is search or a hard contact point to complete the compression phase before firing in unison to push off. I don't think I am overthinking this because if I was, then soccer players and track sprinters would have more padding in their shoes but there is a reason this does not exist.

Having said that, I think that Hokas have their place when I am going to be 'slamming anyway'. They feel awesome after 4-6 hours on the bike and doing transition runs when I am "slamming anyway"...as I said early in this thread, put a Kenyan at mile 20 of an IM marathon, and he's going to be slamming and heel striking too.

See above post, long story short; if you are having ankle foot issues related to motion Hoka's may exacerbate the issue given their height/profile. In terms of impact in an apples to apples comparison with similar strike patterns the Hoka's will likely attenuate more force, which will likely benefit the knee joint the most.

If you can land with a more midfoot pattern in the Hoka's you will not be subjected to longer fulcrums to the extent of heel striking. This is where the conundrum resides as many like Hokas, including myself, because they allow me to run a bit "lazy" and especially when I have tired legs. Fortunately for me, I have no issues at the ankle or foot that get exposed with this lazy patterning.

BTW, they do work very well for folks with forefoot overload problems; such as metatarsalgia, capsulitis�.due to their relatively rigid (fore-aft) structure (low flexibility).

Cheers!

Shouldn't manufacturers have done proper research and found real independent evidence that their products did what they claim before spending so much money on marketing and brainwashing idiots into buying their products?


There was nothing wrong with plimsolls.

One more thing to consider, putting aside the ramp of a show. The padding in a maximally padded Hoka for a 210 lbs runner, may, in effect be the same as a Pegasus for a 140 lbs runner. One thing that I feel running shoe companies don't do is scale the padding for foot size....a women's size 5 and men's size 14 pretty well gets the same thickness sole for most shoe brands. Big guys ended up with really under padded footwear relative to small women.

well, you'd think that as long as the marketing succeeded, the answer would be no - if they got people to buy their product, mission accomplished.
but then, vibram just had to shell out all that $$$ when they lost that lawsuit based on the false claims they'd made. pretty much a matter of arithmetic now - did their claims allow them to sell enough shoes that it was still worth it, even with the lawsuit?

ktm this isn't direct at you, just were I happen to be joining. The whole thread is a bunch of bs technical jargon.....In most cases, the use of Hokas in tri or road events is generally a misapplication. I know Dan has liked them for general running, but I'm guessing he's an outlier.

Go run on rocky, rooty trails in your preferred running shoe for 100 miles with 20k feet each of ascent and descent, take note of when your feet hurt like they never have before (sometime before the end) and how they feel at the end of 100 miles. Then go run the same 100 in Hokas and take note of how your feet and legs feel. This is the what the shoe was made for and a proper application for it. The whole discussion of comparing form and impact forces is a bunch of crap. For a majority of people, roads and distances of less than 50 miles, running in a Hoka is a misapplication of the shoe. It's like you're putting 36" swampers on a Corvette and bitching the car doesn't corner well at the track.

I'll butt in with my 2ct physics/engineering analysis. The sum of the ground-shoe and shoe foot forces have to be equal and opposite. But the forces are not exerted instantaneously. So instead I would state that the integrals of the impulse (Force/time) over the total ground contact time have to be equal and opposite. So a stiff shoe might have a high peak impulse at initial contact and then a low impulse at the end while a cushioned shoe MIGHT reduce the peak impulse and instead spread those impulses over the entire GCT. The way to analyze the difference is to have strain guages and accelerometers in the sole of the shoe or treadmill and then another set on the foot inside the shoe.

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Brian
“Eat and Drink, spin the legs and you’re going to effin push (today).” A Howe

I'm not familiar with the lawsuit or vibram but it serves them right if they were making claims they can't back up.

I grew up in the 1960s and 1970s. We played football, did cross country, athletics, tennis, rode bikes and generally spent most of life in plimsolls or tennis shoes.

I remember a particularly good pair of Stan Smith tennis shoes I wore for over a year.

Obviously we wore football boots for proper games but we played football in the playground before school, every playtime, lunchtime and after school in the park, or played tennis on clay or hard courts or grass courts.

I really don't understand where, why or even when all these cushioned shoes and boots arrived.

I assume it was all marketing and convincing people they needed special shoes for every activity.

Physics - Shmysics. I am completely in agreement with you. It is why I have shocks on my mountain bike too.

Forces travel at the speed of sound. So doing a little bit of math, for say 30mm across a shoe sole at 400 m/s is practically instantaneous-- .000075 seconds.

the forces are exerted on the foot during the entire ground contact time. For my last run the typical GCT was 190 ms. Do have data on your claim that force transmission across a sole is that fast ? If it's true then running barefoot would just like running in shoes. At some level the shoe must change the acceleration at the foot. The question is do maximal shoes exert their forces differently than do minimalist shoes

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Brian
“Eat and Drink, spin the legs and you’re going to effin push (today).” A Howe

With the risk of upsetting Runski with more data (obviously not his cup of tea), to address your supposition; impulse has been shown to differ among shoe types and with orthotics in same runners with controls on conditions (ex. same speed/cadence). Here is an example comparing the same runner shod with 4 different shoes with control for velocity and cadence using an assembled average of 100 strikes per condition:

Yellow: 7oz racing flat
Pink: light weight Stability (Nike Triax) with 200 miles
Blue: light weight Stability (Nike Triax) new out of box
Light Blue: New Balance 990's

Highly reproducible effect showing significant difference in peak vertical GRF and no significant difference in slope analysis (load rate) or stance time. No major point to be made here accept that shoes can attenuate force at varying degrees, however if other factors in the footwear besides cushioning (or lack there of) change pattern then the anticipated effect could be absent or even counter to what is expected. The point is pattern can influence load curve as much as cushioning.

Runski comments are not without merit, but truth is I see plenty of trial runner Hoka converts with same problems as road Hoka as they change the demands regardless of surface.

I realize I tend to nerd out of this stuff and it may only resonant with a few on this forum, but my goal is to make changes or diagnose/treat problems runners have beyond that of just saying "it works for me". The "big ranger" made us all a bit different and the context of what is stated and published needs to be distilled for real-world (n =1) understanding. We all have styles/histories that are more or less amenable to changes from traditional shoes to things like barefoot running or Hokas. The people with no problems are often the most vocal to tell others to HTFU. In my world, I never see these people until they breakdown:)

Cheers!

I do think you are WAY over generalizing the Hoka brand as they have different models now with different "amounts" of cushioning .

I can't read the x axis, but you can nerd me into any analysis paralysis on any topic be it economics, integrals, human physiology, bike geek talk or running mechanics. Basically if there is a conversation striving to understand the fundamentals of how a system works, it does not take much to sucker me in....so looking at these graphs I have a few questions. The racing flat seems to have the highest forces, BUT people talk about ground contact force like it is a bad thing, but I assume like in the case of pedal forcexcrank length x RPM, ground contact forces when running are a good thing if they are applied with the correct vector angle. In other words, I want to maximize my ground contact force at push off....if I look at my deterioration as a runner over time from age 18 3+ decades ago to now, I can keep up my RPM like I was 18....what is worse is stride length which I assume is directly the result of lower ground contact forces. As a track sprinter in youth, we liked hard spikes for sprinting because we lost nothing in the sole....no mushiness....all the force propelled us forward

X axis is time, in this case around .25 second average on impulse. If I recall I hade the speed controlled at 7.5 mph for this runner and cadence was self selected for first trial and then match via metronome.

You are right about higher forces not necessarily being a bad thing, I don't expect Hokas to be worn by any record setting elites on the track or road.

Cheers!

I'll clarify my position. A couple of the Hoka trail models are as close to the the pinnacle of a 100 mile trail shoe as any other shoe is for a different application. The other Hoka models with other amounts of cushioning aren't nearly as relatively as good of shoes vs. their competitors - there are a lot of shoes by other brands that are a lot better suited for road and/or sub-ultra distance (training and racing) than Hokas. The thick mid-sole is generally the wrong tool for the job. I recognize there are a limited number of individuals for whom Hokas are the ideal shoe regardless of application (just as there are people who can't wear them).

The Stinson is becoming (long way to go) to 100 mile trail races what the Pegasus is to road training.

What did Hoka claim that their product would do?

Greater Shock Attenuation.

http://www.hokaoneone.eu/...-Show?cid=technology

Is there scientific evidence they do this, and if so, does the extra cushioning improve running form and reduce injuries, or does the extra cushioning damage running form and increase injuries?

I can't find any links to any scientific studies on their site but they do list a lot of athletes who use their shoes.

http://www.hokaoneone.eu/...ge-Show?cid=athletes

I thought the discussion was about maximalist running shoes in general rather than specifically about Hoka. My objection is to over cushioned over built up shoes in general.

But seeing as you asked I looked them up. I can't find any references to any scientific studies, but to be fair they don't seem to be making any specific claims, other than extra comfort and greater shock attenuation. I assume they have some evidence to back up that claim. What are they comparing against, plimsolls, bare feet, army boots, other running shoes?

Is there any scientific medical based evidence to support the creation of these maximalist Hoka type shoes?


I would have thought so much cushioning would lead to a lack of feel, poor form and the risk of turning ones ankle. I find that the more cushioned the shoe the more my knee hurts. No idea why, possibly I'm so used to minimal or no cushioning the more built up shoe alters my form which stresses the knee more.

I have tried the other extreme Merrell Trail Glove. These are fine, but if you tread on a sharp stone or rock there is so little protection it can be really painful so I won't use them again on trails. The total lack of cushioning seems to suit my running style and hurts my knee less. Imcan only assume the lack of cushioning encourages me to subconsciously alter my form in such a way as to minimise the jarring forces on the joints.

However, Merrell sell it as a shoe for use on trails which is the one place it is totally unsuitable unless you know of trails where there are no socks, stones, roots or bits of wood you might tread on.

As I believe you mentioned earlier, no kinematic data by Davis makes this entire poster presentation mute. Like your graph, our intra-force curve comparisons for each runner tend to show a difference both in the raw data, but also on the perception, with different run shoes. It's why when I have someone on the treadmill and see the data in front of me and just say "run softly," you can watch the N's drop, only to return minutes later due to the habit that is already there....

Believe me- I probably nerd out on this more than even you do- but the best part of all of these discussions is just when people think they have all of the points identified and have "categorized" good vs bad, max vs min, etc, along comes this thing called learned habits, "feelings" and belief, and everyone can watch the process get flipped. The study may show a statistically significant outcome, but in practical application, if someone "feels" the shoe works better and believes it, often it will.

Example- a study in Finland a couple years ago for a group of patients that underwent meniscus surgery repair. Control group had the procedure done. Experimental group had the scope inserted, ID'ed the condition of the meniscus, and were told at the end of the surgery that the knee was now "better than it ever was- good as new." Pain follow-up 12mon later revealed the non-surgery group were still pain free, and the majority of the repaired group were back to higher levels of pain/discomfort. Does it mean we shouldn't spend money on knee repairs? No way- but it does mean there is more going on than some little poster presentation.

Like the graph...thanks for sharing. Do you know the drop and stack heights of the racing flat?

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http://www.reathcon.com

I pulled my notes, this was 2002 or so. The 2 new and old were Nike Span Triax and the flats were a Fila racer (8oz) not sure of profile on these but would guess around 4mm drop.

I also tracked center of pressure and found medial lateral differences among shoes as well with more medial paths associated with NB 990 and used Span triax.

You are correct that in any of these shoes cueing can cause change in peak GRF and joint segment (hip/knee/ankle) doing the work. The cue "run soft" or "make your feet go quiet"; can easily, albeit temporarily, reduce GRF by >10-20% and changing proportional work at 3 major segments is also easily done by cues. Getting the runner to "own" the change, if that is the desire. takes much more. In this case, the runner just ran at fixed speed and cadence without any other cues.

A better way to describe this type of shoe is 'extreme cushioning' vs. 'maximal' cushioning.

Here's the thing about research like this: When you test a group of runners and look at something like impact force while using different shoes, you'll likely see 1/3 of subjects who will have a greater impact for shoe 1 vs. shoe 2, another 1/3 will have a greater impact using shoe 2 vs. 1, and the remaining subjects may have no real discernible difference in impact force between shoes. When stats are computed, this type of result will yield a 'no difference between shoes' result.

But in reality, you have a sub-set of subjects that responded in one direction, and other sub-set that responded in a different direction. This is in line with anecdotal information in this thread in that a shoe style may work for some runners but not others. The trick is trying to match up a shoe with a runner.