will cause you to adopt a very

Today on the Peak Performance blog Amby Burfoot discusses a new study by a research team at the University of Massachusetts headed up by running biomechanist Dr. Joseph Hamill (see abstract here).www.aquarillon.fr The study is an interesting contribution to our knowledge of how running shoes affect the way we impact the ground while Nike Air Max 270 Womens we run, and adds to the growing base of literature showing that running barefoot reduces both peak impact forces and loading rate (how fast the foot impacts the ground) relative to running in shoes. Increased loading rate has been linked to injuries such as stress fractures.What Hamill and colleagues did was to take a group of ten runners who were heel strikers and have them run across a force plate 10 times in each of four footwear conditions. Three of these were 4mm drop shoes (i.e., 4mm heel lift relative to the forefoot) that varied only in the total thickness of the midsole cushioning (all had a thin outsole). In other words, the shoe conditions were as follows in terms of midsole cushion: 4mm heel, 0mm Nike Air Max 95 Mujerforefoot; 12mm heel, 8mm forefoot; 20mm heel, 16mm forefoot. The fourth condition was to have the runners go barefoot.Adidas Superstar Femme None of these runners appear to have been habitual minimalist or barefoot runners, so the study is basically looking at how a runner used to running in a typical modern shoe changes when they go to a 4mm drop shoe (of varying midsole configuration) vs. barefoot. This is short term, immediate change as the runners did not run for an extended period of time to acclimate themselves in any of these shod or unshod conditions (acclimation was only 5-10 minutes prior to data collection).What the authors found was that impact characteristics and knee/ankle stiffness did not vary among the 3 shod conditions. The runners all remained heel strikers in the 3 iterations of the 4mm drop shoes, though details of gait kinematics such Nike Air Max 90 Mujer as stride rate, length, etc. were not reported. However, when running barefoot, which presumably was a novel www.johanweststeijn.nl behavior for these runners, they adopted a midfoot/forefoot strike (I was a bit confused by how they define midfoot since they talk about the foot contacting on the midfoot after which the heel comes down – I tend to think of midfoot being simultaneous contact of heel and the base of the fifth metatarsal). Associated with this is the fact that impact peak and loading rate were significantly reduced, time to reach impact peak decreased, and ankle stiffness increased in the barefoot condition.So what does all of this mean? Basically, if you have been running with a heel striking gait in traditional modern shoes, it is unlikely that going to a 4mm drop shoe will immediately cause you to lose your heel strike. However, going barefoot will cause you to adopt a very different running style whereby you lose the heel strike and adopt Adidas Ultra Boost Herrenimpact moderating Adidas NMD Donne behaviors (e.g., a different footstrike) that reduce peak impact force and the speed with which the foot collides with the ground. These are not entirely surprising results to anyone who has tried running barefoot on a hard surface, but do add to the growing literature showing that running barefoot is very different than running in a shoe with a cushioned heel lift. Whether or not these changes are linked to injury reduction is an open question, and it is possible that a midfoot/forefoot stride could simply shift primary injury locality away from the knee (minimalist runners often report that changing style helps with knee pain) and to the Achilles/calf, ankle, and foot, particularly among those not acclimated to running with barefoot mechanics.What the study does not tell us is whether running in the shoes Nike Air Max 1 Hombre with the 4mm drop midsole Nike Air Vapormax Dames would cause changes in gait over a longer period of time. Most runners who have gone to a more minimalist shoe report that gait change takes time, and that shoes with a lower heel facilitate a change in gait. It doesn’t happen immediately, as this study demonstrates, but it would be interesting to see if patterns changed if these runners were to run exclusively in a 4mm drop shoe for say 6 months. Many so-called minimalist shoes coming out have adopted a 4mm drop midsole or something close to that (e.g., NB Minimus, Saucony Kinvara, Mirage, Fastwitch, etc.), and thus information on potential changes with long term acclimation is much needed.