My Ironman Journey: Running Shock / Impact / Braking

ironman-logo-iconA mate has invited me on a 22 mile run next week. Oh dear. I don’t think I’ve ever run that far.

That got me thinking about my newfound injury-freeness. I probably haven’t changed my technique/strength that much over the last year or so despite a few tweaks probably keeping the dreaded injuries at bay. So once I start cranking up the individual miles to over 15 miles in a session then “Is there any guarantee that my injury woes will NOT come back to haunt me?”

Simplistically: if I’ve improved my impact by 10% but end up running 20% further does the maths still equate to an injury?

Whilst I’ve relished not being injured; on longer runs I have also had the time to muse about how I’m running and also mindful to, at least afterwards, glance at my Shock/Impact/Braking stats on Runscribe PRO (detailed review here, it’s awesome for a data-driven runner).

Here’s the problem I found in a graphic-nutshell:

Friday 13 Jan, 10 miles

Efficiency: Yay !

Shock: Boo

I have delved into the data myself quite a bit more than I’ll write about here but one interesting thing I’ve found with my stats is that when I run faster my shock (definition: runscribe) can be lower for extended periods when I run faster –  which is counter intuitive.

I’ve also found that my shock stats generally seem to be gradually improving with the longer, slower mileage I’m doing. That’s good and how it should be – technical efficiency gains as well as physiological gains.

But I’ll turn this post round to things that might help you rather than just wittering on about me. The following MIGHT be especially useful if you are at all concerned about running injuries from being new to high mileages, or maybe you are just plagued by impact-related injuries.

In my local gym the guy who showed me round last year said how great the CURVE-type, self-powered treadmills are. I confess to ignoring him at the time. Here is the kind I mean.

I recently relented and decided to use one. Mainly because they were right next to the WATT bike and I had had MUCH entertainment watching other people struggle to use them 😉 [schadenfreude to my Austrian friend]

From a CURVE treadmill session last week here is the equivalent high level bit of data from Runscribe. I’m not particularly trying to run differently. The forefoot strike ‘materializes’ probably because the footstrike is occurring further up the curve of the machine. Anyway the real point is that SHOCK is now LOW. Yay! Markedly so.

I’ve repeated this a few times with the same shock levels. That’s quite big change and MUST make a dramatic improvement in keeping the chances of injury lower.

Here’s what I turned in for another short CURVE-treadmill run after a short 1k swim and after relatively tiring Z2 spin of over 3 hours on a hard, wattbike seat. It’s great that the shock is LOW and perhaps not surprising that the efficiency is markedly lower when fatigued.

I don’t really run much on treadmills and the only other non-CURVE treadmill run I did this year also showed LOW SHOCK too. So maybe it’s treadmills in general that can reduce shock? Certainly regular treadmills seem to be cushioned to some degree too.

So what I’m taking out of this is that: in order to reduce the risk of injury I should realise that when fatigued I could well be placing undue stresses on my legs compared to normal. A good means of mitigating this risk seems to be to use treadmills from time-to-time, especially when the risk might be highest such as at the end of brick sessions.

EDIT: I added the following image in mid-March, showing total shock. Start of the run was on a curve treadmill. At the end of the run I was running home on roads. Stark and obvious difference. The interval bits at the end of the treadmill section were where I was trying fairly hard (VO2 effort)…still low impact.


I’ve also used shock-absorbing, Sorbothane-branded insoles like these (below, I used to sort-of work for the company). I’ve always found the heel-only inserts to be effective rather than the full sole insert, as shown. Again that’s counter-intuitive as a mid/forefoot striker wouldn’t land on the heel, so I suspect it’s the slightly higher ramp effect that allows the heel to make contact late in the footstrike to take some of the impact off the calf that probably helped there.

Indeed even when running with new shoes I can tell the difference of the level of cushioning from the standard insole after running as little as over 60 miles on them. They just feel less cushioned. (My Sorbothanes have lasted over 20 years!)

I was also thinking about investigating the maximalist-type running shoes that are becoming popular – I’m thinking particularly of the super-cushioned Hoka One One brand (Hoe Ka Oh Nay Oh Nay, apparently means flying in the clouds, or similar). These seem to be becoming popular in triathlon. Anyone had any joy out of those and still being able to maintain some decent speed?

I’ve managed HM distances in both racing and training with Mizuno’s Waverider 19/20s (detailed review, here) – they’re supposed to be well cushioned but I’ve not found them to be especially cushioned for my mid-foot strike. I like them though and they’re fairly fast.

My Ironman Secret: I end each of My Ironman Journey posts with some sort of secret. I have been known to rummage around the kitchen for performance-enhancing substances. Apart from the relatively obvious coffee tin there is also the baking ingredients cupboard. A good teaspoon of plain old baking powder mixed with orange squash and diluted, actually tastes vaguely nice and when used 3-5 times a day for a few days prior to race day (not on race day) it is supposed to act as an acid buffer (think bicarbonate=alkali, lactic acid=acid, add them together and it’s not as acidic in your blood/muscles). Although also think hydrochloric acid is pretty strong and I’ve no idea how it gets through that and into your bloodstream Seems to work for me tho in shorter races! Get a training buddy to try it first and laugh at how frequently they will visit the bathroom 😉


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2 thoughts on “My Ironman Journey: Running Shock / Impact / Braking

  1. You should be able to go faster in the Hokas, you’ll be an inch taller. Might need some muscle adaption though.

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