Carbon shoe & stress fracture?

Triathlon Forum
1

Just curious on people’s thoughts on this.

I bought endorphin pro and ran in them for a few (4-5) training sessions (6-7 tempo miles) to prep for a 70.3, but most runs I wore other training shoes. These are my first pair of carbon shoes.

They seemed fine, but my left foot felt a little funny for portions of those runs which I attributed to my superfeet inserts. I really don’t know what it was.

Then I used the Pros in the 70.3 and decided not to use my superfeet inserts. First time race day changes are never a great idea. Felt that same funny feeling in my foot during the race but like the other runs it was short lived.

After the race I was limping badly and as it turns out, I have a stress fracture in my fibia.

The fracture could be attributed to a ton of things, but I am wondering if maybe the Pro isnt the right shoe for me or maybe carbon shoes in general or was my body so used to the inserts that it didnt adapt well to not having it? I dont really know how to evaluate whether a shoe is a problem for me as I’ve never had a problem with any pair of shoes I’ve owned before. I am not particular to any brand and have had many different pairs over the years.

Any thoughts are appreciated.

2

I’m not a Dr. and have never stayed at a Holiday Inn, but in my experience going through two stress fractures in college (tibia and femur), they could be blamed on poor training habits over improper shoes. The summer I got my tibial stress fracture I was running solely on a converted railroad, nice and soft crushed limestone. Just ran too much too often. Femur was from too many pounding summer miles as well. In both cases, I ramped up the mileage way too quick.

I will say, after my first 5k in my Vaporfly’s, I had some foot pain that I’ve never had before. Decided no more carbon plated shoes for racing unless I’ve trained in them. I’ve been doing tempo workouts in the Endorphin Speed, and the nylon plate does seem to be less “intrusive” than the carbon plate in the Nike’s. I could see a scenario where a carbon plated shoe could expediate a stress fracture, but it was probably already forming in the first place.

3

if anything the carbon shoes protect more against stress fractures. So the question now is, are you eating enough? Under eating is main cause of most my stress fractures and other injuries

4

if anything the carbon shoes protect more against stress fractures. So the question now is, are you eating enough? Under eating is main cause of most my stress fractures and other injuries

Carbon shoes increase the rate of force development in the tissues, which is a primary cause of stress fractures.

Undereating can definitely contribute to the likelihood of stress fracture, and other injury, but is not causative, and given the timing of the stress fracture… it’s low on the list of things I’d check.

5

I could see a scenario where a carbon plated shoe could expediate a stress fracture, but it was probably already forming in the first place.

Definitely.

Stress fracture incidence increase was my first prediction when I built my own carbon fiber sprint spike plates in 2012.

Stress fractures aren’t going to happen to everyone and most folks won’t have any issue at all. But I bet greater frequency of stress fracture hit the news in 2-4 years.

Perfect storm for creating stress fracture with a carbon plated shoe:
Make a wholesale switch from non-carbon shoes to carbon plated shoes with no transition period between the two shoesMaintain or increase intensity or volume, or both.
I think my exact words to my wife when I saw these hit the market were: “We should invest in bone scan equipment.”

6

I recently bought a pair myself (well May). I did 2 training runs in them (2 and 3 weeks out). One about 6 miles just to see, and the next was a 15 miler final long run before taper for Choo 70.3. Then I raced in them.

To me, they felt like running in mud for the first few miles, but the paces definitely seem faster and easier IMO. I did not have any issues during or after any run. My prior trainer/racer was the Saucony Ride, so no real support there. I did use Superfeet inserts until about 4 years ago as well, but have not in quite some time. I understand the force generation point, but with the foam soles too, they feel so cushy to counteract the firmness of the plate. They do feel like you are falling forward even when standing still though. Love them.

7

Exactly what I thought when I first ran in a pair. I remember noticing the effect of the carbon plate, but also felt like I was coming down a bit harder, or at least, more force was being exerted through the shoe and into my foot/leg. Hard to describe, but I decided it would be wise to really limit the mileage and rotate them in slowly. I was pretty fortunate to escape HS/college without any major lasting issues from my stress fractures, but they ALWAYS occurred early in the season when we ramped up the mileage too fast. Never saw any guys getting them mid or late season, even when the mileage was above 100 per week. Transition to track was also a bit dangerous because you’re doing more speedwork and track workouts in spikes.

I also think that these new super shoes have some folks running harder than they normally would. Another recipe for stress fractures and other injuries.

8

Are you taking at least 5000 IU of D3 per day?

9

If you’re size is 11.5 US, then it’s definitely the shoes and you need to send them to me right away. Whatever you do, do not run in them again, send them immediately. Pm for the address.

Seriously, hope you heal quickly and figure out the main cause.

10

Yeah, I definitely did not undereat throughout my training. I kept joking with my wife that the hidden cost of tri training is the grocery bill.

I followed my training plan to a t and really dont think I amped up mileage too quickly. I really should have done a few more training runs in them before the race and worked them in over a longer period of time.

I am not blaming the shoe, but really just trying to figure out the cause if possible to avoid in future. Wondering if others had any similar experiences with carbon shoes. Only two new things were the carbon shoes and lack of wearing the inserts on race day. Could have just been the overall training load catching up with me, but that seems suspect to happen on exactly race day.

11

every other day only cause thats what the bottle said to do.

12

Ooohhhh, so close. 11

13

Seriously on the nutrition front, you may think you are eating enough but still be under-eating. Have you gotten any bloodwork done recently? The fibula is a weird one to fracture too, usually it would be a foot bone, femur, or tibia if the bones are otherwise healthy.

If bloodwork looks okay, you are probably right about ramping up mileage in the shoes too quick. On the other hand, if the bloodwork has any abnormalities (eg. iron, hormones, etc.) now is the time to address that (while you are recovering and not running)!

14

are you a real doctor??? Also what tissue?

If so you would have a study showing that a carbon plate on a shoe "increase the rate of force development in the tissues "

15

if anything the carbon shoes protect more against stress fractures. So the question now is, are you eating enough? ** Under eating is main cause of most my stress fractures** and other injuries

I’m living proof that you can eat lots and still get stress fractures…lol. I’d say my weight has contributed to them…

16

every other day only cause thats what the bottle said to do.

“The Endocrine Society Practice Guidelines recommend that up to 10,000 IUs daily was safe for adults.”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5402701/
.

17

are you a real doctor??? Also what tissue?

If so you would have a study showing that a carbon plate on a shoe "increase the rate of force development in the tissues "

Haha shots fired! Hoping you’re trolling. But in case not, and for the peanut gallery:

“Real” as in “medical?” If this, then no, I’m not a real Dr.

Or “real” as in actually has PhD and extensive study in relevant field? If this, then yes, I suppose I’m a real Dr. I generally include the “Dr” in my screennames to have reasonable levels of instant credibility on topics on which I opine. I can see that it has backfired in this case.

Also what tissue?
Any tissue involved in the transmission of force through the stance limb during running gait, including primarily muscles, tendons, and bones, but also ligaments, fascia, and a few other things I’m likely leaving out.

If so you would have a study showing that a carbon plate on a shoe "increase the rate of force development in the tissues "
Yes, if this were expert witness testimony, I certainly would.

18

but my left foot felt a little funny …

…and as it turns out, I have a stress fracture in my fibia.

Tibia or Fibula?

Also… can’t really understand why you’d feel a lower leg fracture in your foot rather than your lower leg.

19

Just curious on people’s thoughts on this.

I bought endorphin pro and ran in them for a few (4-5) training sessions (6-7 tempo miles) to prep for a 70.3, but most runs I wore other training shoes. These are my first pair of carbon shoes.

They seemed fine, but my left foot felt a little funny for portions of those runs which I attributed to my superfeet inserts. I really don’t know what it was.

Then I used the Pros in the 70.3 and decided not to use my superfeet inserts. First time race day changes are never a great idea. Felt that same funny feeling in my foot during the race but like the other runs it was short lived.

After the race I was limping badly and as it turns out, I have a stress fracture in my fibia.

The fracture could be attributed to a ton of things, but I am wondering if maybe the Pro isnt the right shoe for me or maybe carbon shoes in general or was my body so used to the inserts that it didnt adapt well to not having it? I dont really know how to evaluate whether a shoe is a problem for me as I’ve never had a problem with any pair of shoes I’ve owned before. I am not particular to any brand and have had many different pairs over the years.

Any thoughts are appreciated.

It is interesting.
My coach, an ex pro duathlete and physiotherapist thinks they are seeing a lot more stress related injuries since carbon plated shoes were released.
I had a nasty one last year, in a weird spot, which we cannot figure out the cause of.
N=1 is not causative evidence, and there will be significant bias in terms of reporting etc, but it would make for a very interesting study.

20

are you a real doctor??? Also what tissue?

If so you would have a study showing that a carbon plate on a shoe "increase the rate of force development in the tissues "

Haha shots fired! Hoping you’re trolling. But in case not, and for the peanut gallery:

“Real” as in “medical?” If this, then no, I’m not a real Dr.

Or “real” as in actually has PhD and extensive study in relevant field? If this, then yes, I suppose I’m a real Dr. I generally include the “Dr” in my screennames to have reasonable levels of instant credibility on topics on which I opine. I can see that it has backfired in this case.

Also what tissue?
Any tissue involved in the transmission of force through the stance limb during running gait, including primarily muscles, tendons, and bones, but also ligaments, fascia, and a few other things I’m likely leaving out.

If so you would have a study showing that a carbon plate on a shoe "increase the rate of force development in the tissues "
Yes, if this were expert witness testimony, I certainly would.

No shots fired. You just make it look like you know what you are talking about but if anyone reads the post you have no evidence just a DR beside your name. plus don’t state and facts to support your N=1.

Please explain how ALL tissues including things you are leaving out "increase the rate of force development in the tissues "

Due to carbon fiber shoe?
Then why do we not see more stress fractures in hockey players with a rock solid soles?
Then why do we see more stress fracture in Ballerina’s with no carbon shoes?

**If anything the carbon shoe allows shitty runners to log more miles and due to them trying harder to go faster So more impacts under poor skill. not the shoe at all. **

**much like a wetsuit the shoe makes to easier so you tend to do more and over do errors which leads to injuries. **