ARTICLE: Natural Experiments

My achilles has been in rapid recovery ever since Sunday’s half-marathon. After two days of slight soreness, it appeared to have gone completely by Wednesday but the last few days I have been able to find a slight sore spot that still get’s irritated when I wear any kind of footwear (this is allegedly because of the shearing force of the heel pressing against the tendon). I’ve been keeping busy doing everything from weights to yoga to kenpo to core synergistics but my most interesting experiments are working further on improving my “natural running technique” and a special type of walking!

Changing patterns

It’s actually quite difficult to injure the achilles tendon, or it should be, for it is the strongest tendon in the body able to resist hundreds of pounds of force.

Over the years I have modified or tried to modify my gait several times from several different angles, from ChiRunning (in 2007) to Functional Movement Systems with Medfit in the recent year. In my early days of running my injuries were the classical type that most modern runners face: plantar, knee injuries, and ankle sprains.

Once I started to run increasingly on my forefoot the pattern shifted. The first thing that happens when you move into a more minimalistic shoe is that your posture returns to a more natural position: imagine standing in your bare feet and then putting a small book under your heels. Because most running shoes have a fairly pronounced drop from the heel to the front, this is actually the posture you adopt when running in such standard runners, unless you are highly trained (people who already possess good technique have been known to run flawlessly even in army boots!).

One of the many effects of this is that your anterior muscles (the quadriceps group), which is designed for braking, is actually used for propulsion, and the propulsive muscles (glutes, calves, hamstrings) are used for braking. So your muscles switch roles from what they were designed to do!

The human body is flexible, so over many years, my muscles, like those of many other runners, just accepted their new job and got on with it. So when I decided to “change the work shift” there was a bit of an outcry particularly from my calves (leading to achilles and tibialis posterior tendon injuries) and feet (leading to metatarsal tip pain). Like in our workplaces, change has to happen slowly if it wants to succeed!

Two specialists, same opinion

John Murphy, from the Carysfort Clinic, had long attributed my injuries to an underdevelopment of calf strength and flexibility as well as an inability to activate the gluteal muscles correctly. Both are very likely a relic of both my lack of sporting background and having grown up running in heavily padded ASICS shoes.

Adri Hartveld, the founder of Healus Technology and a physiotherapist and runner through 37 years, concluded as much when he told me:

From looking at your blog and emails to me I conclude you are keen, knowledgeable by now, but have not yet learned to prevent injury.

The Newton shoes were a good try, but like so many runners without years of forefoot running, your Achilles tendons couldn’t take it.

Healus Technology are currently testing a new shoe design which they hope will help smoothen the transition to a more natural running form, but you need to supplement with proper training as well and at the moment I am testing the strength and form drills in Danny Abshire’s “Natural Running”. Abshire has worked with several of the world’s finest athletes such as Lorraine Moller (co-founder of the Lydiard Foundation and Olympic bronze medallist in the marathon 1992) and Mark Allen, the six-time Ironman world champion.


No, “natural running” doesn’t mean you necessarily have to go all the way, although at least a little bit of barefoot running goes a long way in ingraining the new movement patterns and strengthening the lower leg muscles. As Ken Bob Saxton memorable explains it in “Barefoot Running – Step by Step”, taking your calves out of the shoes is a bit like stepping out of a wheelchair, you are working atrophied muscles.

Transition Plan

Most people will use the transition plan and do some barefoot during it and then settle into their new running form in as minimalist running shoes as they become comfortable in. This use of the technique predates ChiRunning, Pose and Evolution Running by decades and the best example is perhaps this old video of Percy Cerutty training his runners at Portsea, among them Herb Elliot, the 1960 gold medal winner in the Olympic 1500m and world record holder on the 1500m and mile. The lightness and springiness of these athletes is what we would all like to emulate (and it can still be seen in some Western athletes such as Ryan Hall).

I have not been able to fully embrace the training program yet as I have to be cautious with my achilles but I walk in the gravel barefoot every morning and have not worn shoes for seven days solid (relying on Vibram’s). The lack of heel means no pressure on my tendon and not having my heel elevated means more stability and less twisting. Both seems to have contributed to a faster improvement of the symptoms this week. This is anecdotal but in light of the quickness of recovery after the half-marathon, not implausible.

What to wear?

My own plan is to heal the injury first, and then perform all the running the transition program prescribes. My LunarElites and other shoes with a notable discrepancy between heel and front will have to go in favour of shoes that are virtually flat. Shoes like this have long been unavailable, except as fashionable retro shoes like the Onitsuka Tiger, the original shoe brought into the US by Bill Bowerman before he started producing his own. Fell and mountain runners have been luckier as Walshes, traditionally, and now Inov-8s are largely flat to the ground. Since the barefoot craze started the existing light racers have been complemented with a plethora of choices as nicely covered by RunBlogger.

Of my existing collection my Inov-8 X-Talons is an amazing shoe and although I only got to try it in training, I already expect it to bring my descending back to it’s old standard. Compared to the PUMA Trailfox, Salomon’s and Adidas Kanadia it’s a rock solid platform with much more grip. My beloved LunarLites are up in the air, it’s a very pleasant shoe, but I suspect the heel is too high and too unstable which is not good for my tendons. My DS Racers are worn out and need to go to the bin and my Nike MayFlys can’t have too much mileage left on them. My current choice for a replacement is the new Inov-8 Roadlite 155.

Reversing the damage

By not wearing shoes with heels any more the shortening of my achilles can hopefully be reversed but that still leaves me to focus on strengthening the foot and the calves again until they are a level where I can wear a shoe that does not interfere with my gait for the same amount of mileage I have previously been able to handle.

There could be a few difficult moments in this transition, but I feel it’s the right time if I want to ensure a long injury-free career ahead of me. Certainly, a new world opens as you walk on things in your bare feet. You become more controlled in your foot plant and you learn just how sensitive your foot has become to all sensations! (there’s a reason we have reflexology!).

Anyway, hopefully another few days will have the achilles sorted completely so I can start my full retraining.