Barefoot vs Shoes...It's about the strike pattern

“The influence of strike patterns on running is more significant than shoe conditions, which was observed in plantar pressure characteristics. Heel-toe running caused a significant impact force on the heel, but cushioned shoes significantly reduced the maximum loading rate. Meanwhile, although forefoot running can prevent impact, peak plantar pressure was centered at the forefoot for a long period, inducing a potential risk of injury in the metatarsus/phalanx. Plantar pressure on the forefoot with RFS was lesser and push-off force was greater when cushioned shoes were used than when running barefoot.”

takeaways from the study?

• forefoot strike reduces heel impact

• rear foot strike reduces forefoot impact

• forefoot strike increases and prolongs pressures (in shoes) on the forefoot which could potentially cause forefoot problems

• cushioned shoes do not really change impact force but change (reduce) the rate of loading

• in a forefoot strike, pressures are shifted more to the mid foot

want to know more? Join us this Wednesday, December 19th on online.com: Biomechanics 303

Sun X, Yang Y, Wang L, Zhang X, Fu W. Do Strike Patterns or Shoe Conditions have a Predominant Influence on Foot Loading? J Hum Kinet. 2018 Oct 15;64:13-23. doi: 10.1515/hukin-2017-0205. eCollection 2018 Sep.

link to FREE FULL TEXT: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6231350/

Flat Dogs

Take a look at these pedographs. Wow!

• No rear foot heel teardrop.
• No midfoot arch on left foot and minimal on right.
• An elongated 2nd metatarsal bilaterally and forces NOT getting to the base of the 1st metatarsal and stalling on the 2nd: classic sign of an uncompensated forefoot varus.
• increased printing of the lateral foot on the right

Knowing what you know about pronation (need a review? click here) Do you think this foot is a good lever? Do you think they will be able to push off well?

What can we do?

• foot exercises to build the intrinsic and extrinsic muscles of the foot (click here, here, here, and here for a few to get you started)
• perhaps an orthotic to assist in decreasing the pronation while they are strengthening their foot
• motion control shoe? Especially in the beginning as they are strengthening their feet and they fatigue rather easily

The prints do not lie. They tell the true story of how the forces are being transmitted through the foot. For more pedograph cases, click here.

The Gait Guys. Teaching you more about the feet and gait. Spreading gait literacy throughout the net! Do your part by forwarding this post to someone who needs to read it.

The debate continues. More support for mid and forefoot strikers.…

“Forefoot and midfoot strikers had significantly shorter ground contact times than heel strikers. Forefoot and midfoot strikers had significantly faster average race speed than heel strikers.”

We are not saying “better”, but according to this study “faster”!

What is the ideal?  We wish we knew…Biomechanics seem to point to less impact is better, but what is actually best for the individual is probably due to genetics, training, practice, running surface and that individuals neuromuscular competence and ability to compensate.

The Gait Guys. bringing you the facts, even if you or we don’t like them…

J Sports Sci. 2012;30(12):1275-83. doi: 10.1080/02640414.2012.707326. Epub 2012 Aug 2.

Foot strike patterns and ground contact times during high-calibre middle-distance races.

Hayes P, Caplan N.

Source

Department of Sport and Exercise Sciences, School of Life Sciences, Northumbria University, Newcastle-upon-Tyne NE1 8ST, UK. phil.hayes@northumbria.ac.uk

Abstract

The aims of this study were to examine ground contact characteristics, their relationship with race performance, and the time course of any changes in ground contact time during competitive 800 m and 1500 m races. Twenty-two seeded, single-sex middle-distance races totaling 181 runners were filmed at a competitive athletics meeting. Races were filmed at 100 Hz. Ground contact time was recorded one step for each athlete, on each lap of their race. Forefoot and midfoot strikers had significantly shorter ground contact times than heel strikers. Forefoot and midfoot strikers had significantly faster average race speed than heel strikers. There were strong large correlations between ground contact time and average race speed for the women’s events and men’s 1500 m (r = -0.521 to -0.623; P < 0.05), whereas the men’s 800 m displayed only a moderate relationship (r = -0.361; P = 0.002). For each event, ground contact time for the first lap was significantly shorter than for the last lap, which might reflect runners becoming fatigued.

PMID:22857152[PubMed - indexed for MEDLINE]

http://www.ncbi.nlm.nih.gov/pubmed/22857152

Support for a midfoot strike?

“Running with a midfoot strike pattern resulted in a significant increase in gastrocnemius lateralis pre-activation (208 ± 97.4 %, P < 0.05) and in a significant decrease in tibialis anterior EMG activity (56.2 ± 15.5 %, P < 0.05) averaged over the entire stride cycle. The acute attenuation of foot-ground impact seems to be mostly related to the use of a midfoot strike pattern and to a higher pre-activation of the gastrocnemius lateralis. ”

Do these results surprise you? They didn’t really surprise us.

The lateral head of the gastroc is a midstance to preswing stabilizer and works synergistic with the medial head, with the medial head firing earlier. Sutherland talks about these muscles not being propulsive in nature, but rather maintainers of forward progression, step length and gait symmetry. Thinking this through in a closed chain (foot up) fashion, this would counter the inversion moment created by the medial gastroc for supination in the second half of contact phase. If the foot is already partially supinated (as we believe it would be in a midfoot strike), it would have to pre activate.

A decrease in tibialis anterior activity? Sure. If the foot is striking more parallel to the ground, the anterior compartment (including the tibialis anterior, extensor hallucis longus, and extensor digitorum longus) would not have to eccentrically contract to decelerate the lowering of the foot to the ground.

Better? Maybe, maybe not. We are seeing more and more literature about foot strike (if you missed our last few posts, click here, here, here and here), We still maintain that you need a competent lower kinetic chain, including the foot and an intact nervous system to drive the boat.

We remain, handsome, bald and nerdy…Ivo and Shawn

Eur J Appl Physiol. 2012 Aug 9. [Epub ahead of print]

Impact reduction during running: efficiency of simple acute interventions in recreational runners.

Giandolini M, Arnal PJ, Millet GY, Peyrot N, Samozino P, Dubois B, Morin JB.

Source

University of Lyon, 42023, Saint-Etienne, France.

Abstract

Running-related stress fractures have been associated with the overall impact intensity, which has recently been described through the loading rate (LR). Our purpose was to evaluate the effects of four acute interventions with specific focus on LR: wearing racing shoes (RACE), increasing step frequency by 10 % (FREQ), adopting a midfoot strike pattern (MIDFOOT) and combining these three interventions (COMBI). Nine rearfoot-strike subjects performed five 5-min trials during which running kinetics, kinematics and spring-mass behavior were measured for ten consecutive steps on an instrumented treadmill. Electromyographic activity of gastrocnemius lateralis, tibialis anterior, biceps femoris and vastus lateralis muscles was quantified over different phases of the stride cycle. LR was significantly and similarly reduced in MIDFOOT (37.4 ± 7.20 BW s(-1), -56.9 ± 50.0 %) and COMBI (36.8 ± 7.15 BW s(-1), -55.6 ± 29.2 %) conditions compared to NORM (56.3 ± 11.5 BW s(-1), both P < 0.001). RACE (51.1 ± 9.81 BW s(-1)) and FREQ (52.7 ± 11.0 BW s(-1)) conditions had no significant effects on LR. Running with a midfoot strike pattern resulted in a significant increase in gastrocnemius lateralis pre-activation (208 ± 97.4 %, P < 0.05) and in a significant decrease in tibialis anterior EMG activity (56.2 ± 15.5 %, P < 0.05) averaged over the entire stride cycle. The acute attenuation of foot-ground impact seems to be mostly related to the use of a midfoot strike pattern and to a higher pre-activation of the gastrocnemius lateralis. Further studies are needed to test these results in prolonged running exercises and in the long term.

PMID:22875194 [PubMed - as supplied by publisher]

All material copyright 2013 The Gait Guys/The Homunculus Group, yada, yada, yada…

Looks like Newbies are heel strikers

“Nearly all novice runners utilize a rearfoot strike when taking up running in a conventional running shoe. Hereby, the footstrike patterns among novice runners deviate from footstrike patterns among elite and sub-elite runners.”

please take some time to explore the links we put in, as they are germane to the post

The question begs, “Why?”

• do they believe running is merely an extension of walking, and just “speed up” the process?
• are they afraid of going too fast and are using the heel strike to “brake”?
• do they learn to strike differently with more experience? at least one paper eludes to “yes”
• is it “more comfortable” as this paper says it may be?
• If there is a rear foot strike, the foot is poised to be able to pronate to a greater degree. This theoretically means it (ie, the foot) can absorb more shock through this mechanism, although this seemingly contradicts the Lieberman study

This paper certainly had a nice cohort size (> 900 runners) so we can state, at least for this group, that this is not by chance.  When there is a fore foot strike, the foot is more supinated and makes a seemingly “rigid lever”, does this mean there is less shock (perceived or actual) with this foot posture?

Lots of questions. This is only 1 part of the puzzle.

The Gait Guys. Sifting through the literature and giving you the beef

Gait Posture. 2012 Dec 29. pii: S0966-6362(12)00448-1. doi: 10.1016/j.gaitpost.2012.11.022. [Epub ahead of print]

Footstrike patterns among novice runners wearing a conventional, neutral running shoe.

Bertelsen ML, Jensen JF, Nielsen MH, Nielsen RO, Rasmussen S.

Aarhus University Hospital, Aalborg Hospital, Orthopaedic Surgery Research Unit, Science and Innovation Center, Aalborg DK-9000, Denmark. Electronic address: miclejber@gmail.com.

Abstract

INTRODUCTION:

It has been suggested that striking on the midfoot or forefoot, rather than the rearfoot, may lessen injury risk in the feet and lower limb. In previous studies, a disparity in distribution in footstrike patterns was found among elite-, sub-elite, and recreational runners.

PURPOSE:

The purpose of this study was to investigate the footstrike patterns among novice runners.

METHODS:

All runners were equipped with the same conventional running shoe. Participants were video filmed at 300 frames per second and the footstrike patterns were evaluated by two observers. The footstrike was classified as rearfoot, midfoot, forefoot, or asymmetrical.

RESULTS:

A total of 903 persons were evaluated. The percentages of rearfoot-, midfoot-, forefoot-, and asymmetrical footstrike among men were 96.9%, 0.4%, 0.9%, and 1.8%, respectively. Among women the percentages were 99.3%, 0%, 0%, and 0.7%, respectively.

CONCLUSION:

Nearly all novice runners utilize a rearfoot strike when taking up running in a conventional running shoe. Hereby, the footstrike patterns among novice runners deviate from footstrike patterns among elite and sub-elite runners.

Copyright © 2012 Elsevier B.V. All rights reserved.

PMID: 23280125 [PubMed - as supplied by publisher]

all material copyright 2013 The Gait Guys/The Homunculus group. Please don’t lift our stuff without asking and giving credit.

Shoesday Tuesday:

Shoe News You Can Use: The Shank

Look at the “skeleton” in the photo on the left. Now look at the black material above the white area of the midsole (above the outsole) on the right. This is the “shank” of the shoe. The shank is the stiff area of the shoe between the heel to the transverse tarsal joint. It should correspond to the medial longitudinal arch of the foot. It is designed (along with the midsole material: see post here), to provide additional torsional rigidity to the shoe and helps to limit the amount of pronation and motion at the subtalar and mid tarsal joints. It also acts as a “plate” between the outsole and ininsole to provide protection to the foot from rocks, sticks, broken glass, shrapnel and small animals : ).

Not all shoes have a shank, so it may not always be present. We usually dissect shoes sent to us so we can see what they are all about if the manufacturer or rep is unable to provide us with an “exploded” or sectioned model. Look for our take on the new SKORA soon, complete with a dissected version!

The Gait Guys. Making sure you know what you need to so you can make more educated decisions

all material copyright 2012 The Homunculus Group/ The Gait Guys. Please ask to use our stuff. If you don’t, you have to deal with Lee. You don’t want to deal with Lee….

Shoe News you can use….

The Midsole

Last time we talked about the outsole (see here and here if you missed it or need a review). Today we will focus on the midsole.

The Midsole, sandwiched between the outsole and the upper, provides torsional rigidity to a shoe. They can be single (uni) density (left picture) or multiple (middle picture).

Midsole material is very important, as it will accommodate to the load imposed on it from the person as well as any gear they may be carrying. It serves as the intermediary and transducer for load transfer between the ground and the person.  Softer density material in the heel of the shoe, like in the blue lateral side of the shoe in the bottom picture, softens the forces acting at heel strike and is good for impact and shock absorption.

Because the midsole tranduces forces and provides torsional rigidity (picture on right). The stiffer the material, the more motion control it provides.  Midsoles like the one in the center are made with materials of differing densities (white is softer, light grey more dense, dark gray, most dense) to absorb force and decrease the velocity of pronation during heel strike and mid stance, with a firmer material medially that protects against overpronation as you come through mid stance and go through toe off.

Wow. Shoe anatomy for the day. Knew this? Great! Lost? Want to know more? Download our Shoe Fit Certification program by clicking here. You can also email us for more information about becoming IFGEC certified in shoe fit: thegaitguys@gmail.com

Ivo and Shawn. Bald. Handsome. Knowledgeable. The Gait Guys!