martes, octubre 23, 2012

Minimalist Vs modern shoes

ted mc donalkd in turkey

sockwa under 100grs

Minimalists

What is the relationship between the FiveFingers, Brooks’ Pure Connect, the Nike Free 4.0 and the Adizero Hagio from Adidas?

All are considered “minimalist” running shoes. However, their drop ranges from 0 to 12 mm, their thickness is between 3 and 23 mm while their respective weight and flexibility vary considerably.

In my own opinion, the best definition for minimalism bears a qualitative connotation: “The least amount of shoes you can safely wear now.” Given its qualitative nature, we are bound to define tighter parameters in order to quantify the minimalist definition for running shoes.

Up until now, I would have suggested the following set of characteristics for a clear definition of minimalist running shoes:

a drop that was less than 5 mm (heel to toe height differential), a 15 mm stack (thickness at the heel) and a weight lower than 7 oz. (200 g). On the other hand, maximalism would have been defined based on the following:

a 7 mm drop, a 20 mm stack along with a weight exceeding 9 oz. (250 g).

Today, we propose a new formula so that you can rate your running shoes on a scale from 1 to 100

(100 being “extremely minimalist” -bare feet- and 1 “extremely maximalist”).

The range of variation of your final rating will be more or less 5 points regardless of the comfort criteria, which is subjective. The only thing you need to do is to choose a language, then select the tab of your country at the bottom of the formula page,rate your shoes on the 6 criteria set out and there you go! Please note that we have used average values for criteria to which you don’t have the information. The multiple formats of the formula for every country are represented in accordance with their measuring system, currency and the average selling price of a running shoe for each of these countries.

As for health professionals and scientists, you will see that weighting factors have been applied to all criteria as a function of their importance, which is their effect on the body (biomechanics, tissue adaptation, etc.)

http://www.therunningclinic.ca/blog/2012/09/definition-du-minimalisme-defining-minimalism/

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Minimalism for Beginners and Maximalism for Pros

There has been much confusion over minimalist running shoes on the part of running shoe retailers and the general public. While erroneous information mostly conveyed by specialized running shoe companies caused this confusion, it reflects a lack of knowledge with respect to the effect of running shoes on biomechanics and tissue stress.

Below are a few of the arguments that illustrate the gap between science and current practices, which some may see as a paradox. Be that as it may, it is merely the practical integration of what science has put forth thus far.

Reasons why an overweight runner who is not physically fit should run with minimalist running shoes:

1. In order to maximize the joy of running, it is important to reduce the oxygen demand caused by external agents, such as the weight of the running shoes. The latter brings about a surprising energy cost (approximately 1% for every 100 grams added to the running shoes). Needless to say, a total of 3 to 5% may end up being a critical factor in enjoying or hating running.

2. As a result of being overweight, it is essential to develop adequate impact moderating behaviors. In other words, it is crucial to run light. The best way to do so consists in minimizing the interference between the foot and the ground so that the impact is felt under the foot.

3. Such runners are “green” in learning the ropes of biomechanics and mostly fall under the “beginner” category with very few kilometers under their belt. Consequently, it will be necessary very early on in the process to use running shoes that do not interfere with natural biomechanics.

4. The impact forces as well as the stress subsequently applied to the foot (the only area actually protected by maximalist running shoes) are lower at 9 km/hour (6 to 7 min/km) than they are at 17 km/hour (3:45 min/km).

Reasons why a top Kenyan runner could* wear maximalist running shoes while training:

1. His physical condition will allow that extra weight in his shoes.

2. His musculoskeletal development (running bare feet at a young age) in addition to the thousands of kilometers covered have led to efficient, safe and well-established running biomechanics. Therefore, interference caused by maximalist running shoes will have, for some, little influence on their biomechanics, at least on the short term.

3. The impact forces as well as the stress subsequently applied to the foot are greater at 17 km/hour (3:45 min/km) than they are at 9 km/hour (6 to 7 min/km).

4. In some instances during intense training sessions where the body is pushed to its limits, maximalist running shoes could protect a “known weak link”, only if the latter has been identified to be the foot or the calf and other posterior structures of the lower leg.

*(NB: My recommendation for this Kenyan runner would be to perform 100% of his training using minimalist running shoes, although I would not insist as much as in the previous case.)

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Traducción Minimalismo para principiantes y maximalismo para Pros

de Newton Running - España, el El sábado, 20 de octubre de 2012 a la(s) 15:30 · Ha habido mucha confusión sobre las zapatillas minimalistas entre las tiendas especialistas-minoristas y el público en general. Existe muchísima información errónea, sobre todo transmitida por empresas especializadas en calzado deportivo que ha causado confusión, refleja una falta de conocimiento con respecto al efecto del calzado minimalista en la biomecánica y la tensión de los tejidos. A continuación se presentan algunos de los argumentos que ilustran la brecha entre las prácticas de la ciencia y alguna realidad, que algunos pueden ver como una paradoja. Sea como fuere, no es más que la integración práctica de lo que la ciencia ha presentado hasta el momento.

Razones por las que un corredor con sobrepeso que no está en buena forma física debe correr con zapatillas minimalistas:

Para disfrutar corriendo, es importante reducir la demanda de oxígeno causada por agentes externos, tales como el peso de los zapatos para correr. Este último provoca un gasto de energía sorprendente (aproximadamente 1% por cada 100 gramos). No hace falta decir que cifras del 3 al 5% puede llegar a ser un factor crítico entre disfrutar corriendo u odiarlo.

2. Cuando tenemos sobrepeso, es fundamental el desarrollar impacto una pisada adecuada y moderar ciertos comportamientos. En otras palabras, es crucial el correr ligero. La mejor forma de hacerlo consiste en minimizar la interferencia entre el pie y el suelo de modo que el impacto se sienta debajo de La planta del pie.

3. Seguramente estos corredores no llevan demasiados kilómetros de entrenamiento en sus piernas y seguramente serán “vírgenes” en el aprendizaje de biomecánica. Es interesante empezar muy pronto con unas zapatillas que no interfieran demasiado la biomecánica natural del corredor

4. Las fuerzas de impacto, así como el estrés aplicados a la parte posterior de la pantorrila (gemelos, soleo… ) es menor a 9 km / h (6 a 7 min / km) que a 17 km / h (3: 45 min / km)

Razones por las que un keniano podría usar zapatillas * maximalistas para correr durante el entrenamiento:

Por su buen estado de forma un calzado con peso extra no les afecta demasiado Su buen desarrollo locomotor (correr descalzo desde una edad temprana), además de los miles de kilómetros recorridos hace que su biomecánica sea muy eficiente. Por lo tanto, la interferencia causada por maximalistas zapatillas tendrá, al menos a corto plazo, poca influencia en su biomecánica.

Las fuerzas de impacto así como la tensión de gemelos/soleo son mayores a 17 km / hora (3:45 min / km) de lo que son a 9 km / hora (6 a 7 min / km).

En algunos casos, durante las sesiones de entrenamiento intenso donde se pone el cuerpo al límite, las zapatillas maximalistas podrían proteger el conocido como "eslabón débil", es decir si el atleta tiene alguna lesión o sufre en alguna de las estructuras posteriores de la pantorrilla (aquiles, soleo…)

http://www.facebook.com/notes/newton-running-espa%C3%B1a/minimalismo-para-principiantes-y-maximalismo-para-pros/441916529177764

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modern running shoes vs minimalists

Very few scientists or health professionals still defend modern running shoes (big bulky ones). However, a one of them is a very tenacious, but good expert in the subject; Kevin A. Kirby, Podiatrist (Adjunct Associate Professor, Department of Applied Biomechanics, California School of Podiatric Medicine) keeps exposing himself as a fervent modern running shoes advocate.

I know Kevin from blogs like Podiatry Arena and Podiatry Today, and I have to say that his elaborate knowledge on questions surrounding running shoes make him a great debater. I don’t agree with some of his opinions but I respect the man and the ideas he scientifically defends.

Kevin recently published an article on

http://www.podiatrytoday.com/barefoot-versus-shod-running-which-best

and already had exposed « the 10 facts that barefoot running defenders never speak about ». Here are our answers in blue!

Kevin A. Kirby:

Here are some facts that the barefoot running advocates seem to never mention:

1. All the current world records in track, road racing and cross-country were set, not barefoot, but in shoes.

A : With very minimalist shoes for 90% of them. (zero-drop for spikes, very light and no support for all these shoes)

2. No international marathon has been won by a barefoot runner (running the whole race barefoot) for the last 50 years.

A: That’s a proof that modern men are completely addicted to shoes and to a certain degree of protection… it’s not the proof that it’s better (Same parallel with obesity… normality and generality don’t mean better… 60% of north-Americans are overweight… and it isn’t something I recommend.)

3. « Minimalist shoes » are nothing new and they have been continuously available in running shoe stores for the past 40 years. They were called « racing flats » for the past40 years.

A: Yes, but the running shoe retailers recommend this type of shoe only to the skinny fast young runners… 3% of the runners and 3% of sales up until 2 years ago. Good thing that this new trend of « Minimalism » is changing minds, and is allowing for a better open-mindedness from retailers!

4. Abebe Bikila won the 1964 Tokyo Olympic Marathon, breaking the world record in a time of 2:12:11, while in shoes, running 7 seconds per mile faster than he had in the 1960 Rome Olympic Marathon where he ran barefoot.

A: Indeed, and 4 years later he was injured (stress fracture caused by his new heel strike pattern induced by the shoes?

Don’t know… just guessing ) . You can compare track performance… but not different marathons (environmental conditions, hills, …).

5. Zola Budd, who broke the women’s 5,000 meter world record while barefoot now prefers shoes saying:

“: “I no longer run barefoot. As I got older, I had injuries to my hamstring. I found that wearing shoes gives me more support and protection from injuries.”

A: Personal feeling and maybe misconception… Some runners successfully switched to barefoot running for exactly the same reasons! Do you think that shoes decrease mechanical stress on the hamstring?

Do you think that big bulky shoes decrease the stress on any other part of the body than the foot and the lower part of the leg?

6. Split-toe, thin-soled running shoes, such as the Vibram FiveFinger are nothing new. The 1951 Boston Marathon was won by a Japanese runner, Shigeki Tanaka, wearing a split-toe, thin-soled running made by Onitsuka Tiger (now Asics).

A: No comment… what’s the problem?

7. Six scientific research studies published in peer-reviewed journals show that barefoot running increases the vertical loading rate -VLR- compared to shod running

(Dickinson, 1985; Komi, 1987; Lees 1988; Oakley, 1988; DeClercq, 1994; DeWit, 2000).

A: You forgot Cole-1995, De Koning-1993, McCarthy-2011(UP), O’Leary-2008 for your assumption … but also other studies saying the opposite (Lieberman 2010, Divert 2004, Hamill 2011). Most of the studies showing an increase of VLR are done with runners used to shod running… suddenly running barefoot… few trials on a short runway of 20 to 30m… with often no change (or not enough) in their biomechanics (most of the time, these runners, keep heel striking, voluntarily or not). Runners used to run barefoot have clearly less VLR (Lieberman 2010, Squadrone-2009).

8. Barefoot running causes increased tibial acceleration (McNair PJ, Marshall RN: Kinematic and kinetic parameters associated with running in different shoes. Br J Sp Med, 28:256-260, 1994).

A: One more time, a single study with 10 people used to shod running… with small and subtle kinematic differences between barefoot and shod conditions. Why not to name ‘Shorten 2002′ (review) or ‘Kerrigan 2009′ (shoes increase joint torques at the knee and hips) or ‘Braunstein 2010, Shakoor 2006, Bergmann 2010′ (shoes increase stress on the knee) or other studies using extensiometers, intra-articular chips, accelerometers,… and showing different results (Rethnam 2011, Hamill 2011, Lieberman 2010, Bergmann 2010, Divert 2004, 1996 Hennig).

9. The world’s leading researcher in running biomechanics and running shoe biomechanics, Dr. Benno Nigg, did a prospective study that found no significant differences in frequency of running injuries between subjects with high-, medium-, or low-impact peaks and that subjects with higher loading rates had significantly fewer running-related injuries when compared to subjects with lower loading rates (Nigg BM. Impact forces in running. Current Opinion in Orthopedics, 8(6):43-47, 1997).

Dr. Nigg further claims that “Currently, there is no conclusive evidence that impact forces during heel-toe running are responsible for development of running-related injuries.” (Nigg BM: Biomechanics of Sports Shoes.

University of Calgary, Calgary, 2010. p. 32.)

A: I agree with most of Nigg’s statement… but still we need to consider all the other studies on that topic, especially those made after the publication of his book (2011-Zadpoor, 2010-Davis(UP)… and 2006-Millner, 2006-Dixon, 2005-Zifchock, 2005-Divert, 2005-Dallam, 2005-Hreljac, 2004-Arendse, 2003-Mercer, 2000-Hreljac, 2000-Razeghi).

Just for your information, the conclusion of Dr Nigg is also suggesting the non-effect of shoe cushioning to prevent injuries.

10. Barefoot running increases internal tibial rotation vs shod running, meaning that rearfoot pronation and injuries associated with excessive rearfoot pronation may be increased in barefoot running (Eslami M, Damavandi M, Allard P: Foot joints and tibial kinematic coupling patterns during stance phase of barefoot versus shod running. J Biomech, 39:S183, 2006.
Fukano M, Nagano Y, Ida H, Fukubayashi T:

Change in tibial rotation of barefoot versus shod running. Footwear Science, 1:19-23, 2009.)

A: Pure correlation… not causation! Pronation and internal tibial rotation are not clear causes of injuries

(2009(RS)-Barton, 2009(SR)-Zammit, 2008-Grau, 2008-Donoghue, 2008-Srcevic, 2007-Wilson, 2006-Cheung, 2005(R)-Hreljac, 2005(R)-Knutson, 2002(R)-Gurney, 2001-Nigg, 2000-Hreljac, 2000-Razegi, 1998-Hintermann, 1997-Wen, 1997-Stergiou, 1994-Hintermann).

Some authors think that shoes increase pronation

(Stacoff-2001, Hamill-1992, Heil-1999) and can change the knee alignment (Radzimski(RS) 2011, Chen 2010, Kerrigan 2009, Burkett 1985, Chen 2010)

11. There is not one shred of scientific research that shows that running barefoot or running in minimalist shoes reduces the risk of injury. However, the rate of stress fractures in the metatarsals is alarming of those runners who switch to running barefoot or running in “minimalist shoes”, such as the Vibram FiveFingers.

A: Why alarming? Anecdotic cases without scientific evidence (except a study on 2 subjects: Giuliani 2011) are used to draw attention away from the fact that promoting modern running technologic and maximalist shoes (90% of the current market) is not supported by any scientific evidence showing their benefits in preventing running injuries.

That being said, I am convinced that a too quick transition towards minimalism or barefoot running can be harmful for tissues weakened by frequent wearing of modern maximalist running shoes.

Kevin A. Kirby, DPM
 Adjunct Associate Professor
Department of Applied Biomechanics
California School of Podiatric Medicine

A: Blaise Dubois, PT, MSc Candidate, RCAMT, SPD

http://www.therunningclinic.ca/blog/category/chaussuresshoes/

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