I recently participated in a barefoot running study at the University of Florida Department of Orthopaedics and Rehabilitation.  As of the time I started writing this blog post, the study is still seeking participants (http://www.ortho.ufl.edu/research/studies/barefoot-running).

The stated purpose of the study is to compare how many calories are used and how much force is produced when the feet make contact with the ground while barefoot compared to wearing cushioned shoes.  Eligible test subjects are trained runners who have a mid-forefoot run pattern (where the middle foot or ball of the foot touches the ground first compared to the heels landing first) and meet the following criteria:

- Men and women 18-60 years old.

- A verified running foot striking style of mid-forefoot strike

- Run on average at least 20 miles/week.

- Able to run for at least 20 minutes at one session.

- Free of any ofthopedic limitation (e.g. acute injury to the lower limb, hip or back).

- Must have, and run in, cushioned running shoes at least once per week.  

 When I first heard of the study a while ago I didn't think I met the criteria (I either wasn't hitting the mileage or I was doing all of my runs in minimalist shoes). More recently I have been doing bigger mileage and running in my Altra Instincts at least once per week and I felt like I would be a really good fit for the study. 

The lure for participants is that they receive a copy of much of the collected data and the high speed video footage from the Biomechanics and Motion Analysis Laboratory / UF Sports Performance Center.

Here is a picture of me wearing the metabolic gear, motion tracking dots, and with my Altra Instincts all taped up to cover the reflective surfaces:

The red light in the background is one of the many cameras used for motion capture.  More on that in a moment...

Besides the running data collected, the researcers performed a BOD POD body composition test. I fell into the "Moderately Lean" category (body fat 12 - 20%) which means "Fat level is generally acceptable for good health" according to the info sheet I was given. There are three categories with less body fat than me, "Lean", "Ultra Lean" (5 - 8%), and "Risky" (less than 5%). Elite runners tend to fall into the "Ultra Lean" category. I'm still trying to drop a few more pounds (in order to help my race times) and this would put me safely into the Lean category, absolutley not "too skinny" as some observers have tried to tell me.  I forgot to suck in my gut for the picture above but I suppose there is something to be said for honest photographic evidence.

As mentioned, I was decorated with reflective dots all over my body and my feet.  The dots are actually shiny round balls.  The researchers also taped my bare feet to prevent damage from the treadmil. This was required by the study review board due to injury of the first particpant in the study.  I resisted due to the chance that the tape would affect my stride, but in the end they gave me a minimal taping job that I feel did not hinder my running technique.

Here are my Altra Instincts with the motion tracking balls attached and before tape was applied to the shoes:

Unfortunately I did not get a copy of the force plate and force pad data, nor did I get to spend very much time viewing it at the lab.  My brief encounter with the data seemed to indicate that my cushioned shoes were helping to dissipate some of the force, at least to the pad. The nice wide outsole of my Altra Instincts probably provided some benefit in these measurements (they kind of look like snow shoes compared to my bare feet).  I also did not get a copy of the motion capture data, or any animations using the data.  It's my understanding that those data are locked up in an expensive proprietary software package. Lame.

And now... the videos!  All videos are of myself (Dan Stoner) running on a treadmill at 7 Miles per hour (approximately 8:30 per mile pace). For me, this is a moderate pace for a long distance run. The rearchers did not give a lot of guidance about pace selection, they just said to pick something I could definitely maintain for 20 minutes.

The first video is barefoot running, zoomed in view from the rear.  The only issues that jump out at me are the slight wobble that occurs sometimes on the lift of the foot, and the foot is not always pointed straight forward so I have some wasted motion.

The next video is barefoot from the side.  The video helped me notice that I have completely lost the technique of "falling foward".  My posture has apparently drifted towards being very upgright.  Not nearly as bad as slouching, but I think this has been causing me to forcibly pull myself through each stride.  In the future I wll be working to incorporate a slight lean from the ankles.

The next video is shod (wearing Altra Instincts) from the side.  Both side videos show that my left arm does not pull back quite as far as the right arm.

The next video is from the rear.  This time my upper body is visible.  I can see from this video that my arm carriage is not symmetric.  My right elbow clearly sticks out more than the left. This also may contribute to a slight side-to-side sway of my head and shoulders that is not very visible in the video but stood out in the motion capture analysis.

And finally, the last video is shod from the rear.  The most notable issue with the my shod running is that the wobble as I lift each foot is slightly more pronounced than when I am barefoot.  The extra weight of the shoe at the end of that long lever called the leg may be affecting the foot's motion.  But otherwise, I seem to run pretty much the same in my Altra Instincts as when I am barefoot.

Some of the data and graphs that were given to me confirm that there is a slight asymmetry in my stride (stride length, time on the ground, angle of pelvis, etc).  Whether the arms are causing this is not clear. Over the coming months I will be trying to implement the following changes to my stride:  1. working to keep my right elbow in closer to my body  2.  Learning to "fall forward" again rather than pulling myself through each stride.

The Data!  Here are some interesting data points to compare my treadmill runs while barefoot vs. shod in cushioned shoes.  As mentioned above, my runs were at 7 miles per hour (approx. 8:30 per mile pace) for 20 minutes (after a short warmup period).  Based on heart rate and perceived effort, I remained in the aerobic zone for the entire run:

The apparent conclusion is that running barefoot is "harder" than running in cushioned shoes.  Even though I am an avid minimalist and barefoot runner, I don't mind this outcome.  In fact, it shows that training barefoot gets more bang for the buck (more calories per minute). At the same time I continue to feel that barefoot running helps to keep the injuries away. As observed in the videos above, my form seems to be affected slightly by wearing shoes (the wobble).  I seem to be having some success by keeping a rotation of barefoot, minimalist, and cushioned shoes. When it comes race time, I'm happy to get the benefit from lightweight cushioned shoes. Besides the friction barrier that lets me forget about my feet, the shoes might just make running feel a tiny bit easier.

But the next question is whether this study really demonstrates something, or whether there are enough outside factors to account for a few beats per minute and a few total calories difference.  I'll be interested to read the full study when it comes out.

The videos above were edited down to a little over 30 seconds each using the OpenShot Video Editor on Linux.