Forefoot strike running: Do you have enough calf muscle endurance to do it without a cost ?

Below you will find an article on footwear and running. Rice et al concluded that 

“ When running in a standard shoe, peak resultant and component instantaneous loadrates were similar between footstrike patterns. However, loadrates were lower when running in minimal shoes with a FFS (forefoot strike), compared with running in standard shoes with either foot strike. Therefore, it appears that footwear alters the loadrates during running, even with similar foot strike patterns.

They concluded that footwear alters the load rates during running. No brain surgery here. But that is not the point I want to discuss today. Foot strike matters. Shoes matter. And pairing the foot type and your strike patterns of mental choice, or out of natural choice, is critical. For example, you are not likely (hopefully) to choose a HOKA shoe if you are a forefoot striker. The problem is, novice runners are not likely to have a clue about this, especially if they are fashonistas about their reasoning behind shoe purchases. Most serious runners do not care about the look/color of the shoe. This is serious business to them and they know it is just a 2-3 months in the shoe, depending on their mileage. But, pairing the foot type, foot strike pattern and shoe anatomy is a bit of a science and an art. I will just mention our National Shoe Fit Certification program here if you want to get deeper into that science and art. (Beware, this is not a course for the feint of heart.)

However, I just wanted to approach a theoretical topic today, playing off of the “Forefoot strike” methodology mentioned in the article today.  I see this often in my practice, I know Ivo does as well. The issue can be one of insufficient endurance and top end strength (top end ankle plantar flexion) of the posterior mechanism, the gastrocsoleus-achilles complex. If your calf complex starts to fatigue and you are forefoot striker, the heel will begin to drop, and sometimes abruptly right after forefoot load. The posterior compartment is a great spring loading mechanism and can be used effectively in many runners, the question is, if you fatigue your’s beyond what is safe and effective are you going to pay a price ? This heel drop can put a sudden unexpected and possibly excessive load into the posterior compartment and achilles. This act will move you into more relative dorsiflexion, this will also likely start abrupt loading the calf-achilles eccentrically. IF you have not trained this compartment for eccentric loads, your achilles may begin to call you out angrily. Can you control the heel decent sufficiently to use the stored energy efficiently and effectively? Or will you be a casualty?  This drop if uncontrolled or excessive may also start to cause some heel counter slippage at the back of the shoe, friction is never a good thing between skin and shoe. This may cause some insertional tendonitis or achilles proper hypertrophy or adaptive thickening. This may cause some knee extension when the knee should not be extending. This may cause some pelvis drop, a lateral foot weight bear shift and supination tendencies, some patellofemoral compression, anterior meniscofemoral compression/impingement, altered arm swing etc.  You catch my drift. Simply put, an endurance challenged posterior compartment, one that may not express its problem until the latter miles, is something to be aware of. 

Imagine being a forefoot striker and 6 miles into a run your calf starts to fatigue. That forefoot strike now becomes a potential liability. We like, when possible, a mid foot strike. This avoids heel strike, avoids the problems above, and is still a highly effective running strike pattern. Think about this, if you are a forefoot striker and yet you still feel your heel touch down each step after the forefoot load, you may be experiencing some of the things I mentioned above on a low level. And, you momentarily moved backwards when you are trying to run forwards. Why not just make a subtle change towards mid foot strike, when that heel touches down after your forefoot strike, you are essentially there anyways. Think about it.

Shawn Allen, one of The Gait Guys

Footwear Matters: Influence of Footwear and Foot Strike on Loadrates During Running. Medicine & Science in Sports & Exercise:
Rice, Hannah M.; Jamison, Steve T.; Davis, Irene S.

http://journals.lww.com/acsm-msse/Abstract/publishahead/Footwear_Matters___Influence_of_Footwear_and_Foot.97456.aspx