Tuesday, October 13, 2009

Ankle Sprains & Footware

Some great stuff out of the '09 International Ankle Symposium from this past summer:

"CLAIM AND COUNTERCLAIM: FOOTWEAR AND FOOT AND ANKLE MECHANICS DURING PHYSICAL ACTIVITY"
RICHARD SMITH, Discipline of Exercise and Sport Science, University of Sydney, Sydney, Australia.

Compared lower leg & foot mechanics during barefoot running to running with so called "neutral" & "dual-density" shoes. Their conclusion was, "The change is not always that which was intended by the shoe maker. The ground/shoe/rearfoot interface with the shank can be the
promoter or recipient of the motion drivers." Across the board there was more ankle motion/less mid-tarsal joint motion with the shoes. In the "stability" shoes, they noted tibial external rotation began much earlier than in barefoot-even while the knee was still flexing at ground contact. What do you think? Can this make one more susceptible to ankle sprains?

3 comments:

JH said...

Joe,
By "stability" do you mean motion control? If so then isn't the ER of teh tib what we desire? the type of foot using a motion control shoe would be an overpronator right? Then yes that ER earlier would be a good thing as it would help to decrease or at least delay overpronation. On another note, the claim that shoes promote heel strike as opposed to forefoot strike I agree with. by heel striking 2 of the most important joints in running are left out of the equation in terms of force absorption. Those joints being the ankle and toes. (ok the toes count for more than 1 joint).

Joe Przytula said...

Humm, I can see slowing down, or limiting IR. But if these researchers are correct, we're talking abnormal biomechanics. If the knee is still flexing, then it's probably safe to assume the trail leg has not come through yet to lock up the front side. I think that tib should be in some degree of IR at this point. The Aussies are making me think again.

JH said...

True dat!

I wasn't considering the deceration action just after ground contact. Yes IR would be most necessary. However I'm confused as to how ER could even happen at the point of grouind contact even with a shoe that promotes ER of teh tib?

I guess it's very probably when you consider the mid foot contacts the gound first.

Joe, Thanks for keeping me on the straight and narrow. :)