Friday, January 27, 2012

Effects of Footwear and Stride Type on Running Economy



Here is is study looking at how running economy differs in habitual minimalist or barefoot runners if they are in minimalist shoes or in a more standard running shoe. 


The researchers found that runners were 2.41% more economical in a minimal shoe when forefoot striking and 3.32% more economical in a minimal shoe when rearfoot striking. 


The conclusion was that these runners in minimal shoes were more economic than runners in traditional shoes. 


However, something bothers me. I quote "We measured the cost of transport (mlO2/kg/m) in subjects who habitually run in minimal shoes or barefoot while they were running at 3.0 m/s on a treadmill during forefoot and rearfoot striking while wearing minimal and standard shoes


Bingo. 


The runners tested were habitual barefoot or minimalist runners. That only shows me that we as runners become more efficient at what we most often do. 


Habitually, I...

  • do my long runs at a 9-10 minute pace depending on terrain and distance. If I were to deviate from this, going slower or faster, my economy would be negatively impacted.
  • have executed the the majority of my training on flat roads. If I go to a trail I use different stabilizer muscles, may land slightly differently, etc. All negatively impacting my economy. 
  • use minimalist Skora shoes. Like this study clearly demonstrated, if I was to go for a run in a pair of Brooks Beasts, my economy would take a hit.
  • run longer and slower distances. I would be more economical running a marathon than a 5k. 
  • run at a 94 steps per minute pace. Any slower or faster and I would be less economical.



Unless I am missing something (please tell me if I am), the study does nothing to show that minimalism/barefoot is better than standard shoes. Only that if you habitually do something, you will become less economical if you make a sudden change.  


Med Sci Sports Exerc. 2012 Jan 3. [Epub ahead of print]

Effects of Footwear and Strike Type on Running Economy.

Source

Department of Human Evolutionary Biology, Harvard University, 11 Divinity Avenue, Cambridge MA 02138, USA.

Abstract

PURPOSE:

This study tests if running economy differs in minimal shoes versus standard running shoes with cushioned, elevated heels and arch supports, and in forefoot versus rearfoot strike gaits.

METHODS:

We measured the cost of transport (mlO2/kg/m) in subjects who habitually run in minimal shoes or barefoot while they were running at 3.0 m/s on a treadmill during forefoot and rearfoot striking while wearing minimal and standard shoes, controlling for shoe mass and stride frequency. Force and kinematic data were collected when shod and barefoot to quantify differences in knee flexion, arch strain, plantarflexor force production, and Achilles tendon-triceps surae strain.

RESULTS:

After controlling for stride frequency and shoe mass, runners were 2.41% more economical in the minimal shoe condition when forefoot striking and 3.32% more economical in the minimal shoe condition when rearfoot striking (p<0.05). In contrast, forefoot and rearfoot striking did not differ significantly in cost for either minimal or standard shoe running. Arch strain was not measured in shoes condition but was significantly greater during forefoot than rearfoot striking when barefoot. Plantarflexor force output was significantly higher in forefoot than rearfoot striking, and in barefoot than shod running. Achilles tendon-triceps surae strain and knee flexion were also lower in barefoot than standard shoe running.

CONCLUSIONS:

Minimally shod runners are modestly but significantly more economical than traditionally shod runners regardless of strike type, after controlling for shoe mass and stride frequency. The likely cause of this difference is more elastic energy storage and release in the lower extremity during minimal shoe running.



Thursday, January 26, 2012

Do Epic Shit


Stop waiting for permission to do something awesome. - Richardo Bueno

The Unchained Movement



I have never ran for any type of cause before. Someone recently asked me why, and I said I simply have not found one I liked enough yet. I am not a fan of raising money for research or awareness for various diseases or conditions because I believe if the public was properly educated the majority of those charities, and the diseases, would be almost non existent. This is due to the fact that the majority of diseases of modern man are a result of lifestyle choices. 


Recently I became aware of UNCHAINED and how real of an issue domestic sex trafficking is here in the US. Before doing my research, I thought it was just something that happened when pretty blond American girls travel alone to Paris and run into Albanian gang members. 

If you want some quick information about the subject, check out this video below.


UNCHAINED seeks to educate the public about the issues of domestic sex trafficking without discrimination. Domestic sex trafficking is a growing billion dollar industry that can effect all walks of life. Our focus is to target all who could be affected by this issue or who are unaware of its effects. We will market to teens, college students, teachers, youth groups, survivors, victims, social service agencies, women’s rights groups, law enforcement agencies, legislators and advocates for hope and justice. As the sex industry continues to grow, a stronger need for advocacy, education and awareness must be ready to address the growing demand.


5 Projects of UNCHAINED
Establish a residential treatment center for young girls who have been victims of domestic sex trafficking.
Develop a mobile awareness event to tour the U.S.
College Campus Awareness Events
Provide community professionals with training and tools to identify, support and care for victims of domestic sex trafficking.
Awareness and Education through special video projects



As of writing this, their website is in construction, but they have  been active at their Facebook page.


During 2012 I hope to use a race or two as fundraisers. I have some timed events where the goal is to run as far as possible in 12 or 24 hours. Doing a donation per mile or lap for that would be fun. 


My donation page is located here: ( don't mind the massive heel strike :p )


Thanks for reading!

Shit Ultrarunners Say

And I think I said half of these during yesterday's run :p

Sh*t Triathletes Say

Wow, I've said about 95% of these in the past 5 years...