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Lighter shoe makes running easier - an experiment! (Read 1388 times)

    I agree that lighter shoes can allow you to run faster (just imagine strapping on 1 pound weights on your ankles and trying a sprint).  On the other hand shoes with more cushioning might mean less pounding stress and fresher legs after 20 miles.  So more cushioning in shoes (ie heavier shoes) might actually allow you to run a long race faster.

     

    So, if I can rephrase, the question is: What results in fresher legs after 20 miles?

     

    Is it the physical impact of foot on the ground that causes the loss of freshness (which more cushioning might reduce) or is it the fact that your legs have had to do less muscular work throwing your foot forwards?

     

    When you run at 10 miles per hour you will be accelerating your foot to about 20 miles per hour before it stops again with each stride. My guess is that this repeated acceleration is what often leads to fatigue. Of course a lack of cushioning might be a problem too - especially for heavier runners.

      So, if I can rephrase, the question is: What results in fresher legs after 20 miles?

       

      Is it the physical impact of foot on the ground that causes the loss of freshness (which more cushioning might reduce) or is it the fact that your legs have had to do less muscular work throwing your foot forwards?

       

      When you run at 10 miles per hour you will be accelerating your foot to about 20 miles per hour before it stops again with each stride. My guess is that this repeated acceleration is what often leads to fatigue. Of course a lack of cushioning might be a problem too - especially for heavier runners.

       

      One theory: over time you adapt to the stresses that running subjects your muscles, tendons, etc. to. If you change shoes you're changing those stresses, and your body needs to be able to gradually adapt to those changes. In the meantime you're subjecting yourself to stresses that you're not trained for and so the muscles etc. will fatigue. Given time and training you can probably build up the strength in the right places to deal with the change - but better do it gradually if you want to avoid injury.

       

      Different people are better able to adapt quickly and in any case have more natural strength and/or suppleness. Unfortunately as we get older it becomes harder...

        Yes, it is possible that different shoes change the balance of forces that the various muscles have to produce. I wonder how much of an issue that it? Whilst thinking about the benefits of switching to lighter shoes I hadn't considered that having certain muscles trained for heavier shoes might be a drawback. I was tending towards the 'train in heavy/cushioned shoes and race in light ones' philosophy. But, I guess you are suggesting that one should train in the same shoes that one races in.....that is going to get expensive....

           

          I think I'd give my right arm to be able to run a marathon at a HR of 175....  Wink

           

          I just want to say, for the record, my marathon HR average is ~175-178...but I'm an hour slower than you.  :-P

           

          Anecdotally, when I wear shoes that weigh "more" than what I'm used to (5-6 ounces now), my cadence drops by around 5% (this for a 9-10 ounce shoe).

          "When a person trains once, nothing happens. When a person forces himself to do a thing a hundred or a thousand times, then he certainly has developed in more ways than physical. Is it raining? That doesn't matter. Am I tired? That doesn't matter, either. Then willpower will be no problem." 
          Emil Zatopek

            I wonder whether anyone is interested in a little experiment I did yesterday in an attempt to quantify the likely benefits of lightweight running shoes compared with a more cushioned training shoe.

            I have written the results up in my blog.

            http://christofschwiening.blogspot.co.uk/2012/05/quantification-of-reduction-in-effort.html

            Any comments and suggestions welcome!

            An interesting study and I'll totally agree with the concept.

             

            When they had that study on why Kenyans are a better distance runner, their conclusion was that they have "skinny calves".  It sounds almost like a joke but the rationale was that if you have extra weight below your knee, your running economy, measured in the amount of oxygen being used, goes out the window.  That was done something like 10-12 years ago.  When I heard about this and talked to Peter Snell, he just laughed about it and said; "Have you seen my calves?"  

             

            I was reading a book written by a gentleman by the name of Mimura who had been custom-building shoes for ASICS for who's who in distance running in the past 40 years.  In the mid 1980s, they tried to cut down the extra weight.  They were coming up with some super light weight shoes and, he said, he recognized that, depending on their running style, some runners didn't like the shoe that's too light.  He said that there's a certain "pendulum effect" (particularly below the knees) and, for more of a rhythm runner, if you have some level of weight on your feet, you get good pendulum effect and run on a good rhythm.  In other words, is "the lighter the better?"  Yes, to a certain degree.  I'd go with "200g is better than 350g", yes.  Is 120g better than 180g?  Well, not sure...  Someone already mentioned about some degree of shock absorption.  If straight forward "less is better", then we all want to run in bear foot.  I don't--I run in shoes.  Not that I don't believe in bear foot running.  But I believe in the right shoes.  Certainly the weight is a big part of it but not everything.

             

            HyperSpeed happens to be one of my very favorite shoes--for both training and racing.  I wouldn't necessarily consider that as a minimalist shoe.  I don't know what's the lightest shoes in the market--maybe Mizuno Musha?  I've got this pair from ASICS years ago; their construction is very similar to what adiZero feather is; there are tons of missing parts on the midsole and they ARE super light.  Insole is not even cushioned at all.  I remember their ad (in Japan); "If you only want the light weight, it doesn't have to be ASICS..."  There's more to lightness...or the right shoes.  Some level of cushion, yes (not too much).  Also, to me, the shape of the shoe is extremely important--what's the point of having some expensive gimmick if the shoe doesn't even fit my feet?  

             

            Also, the measurement of HR is a tricky thing too.  Years ago when I was working for Breathe Right Nasal Strip, they had a clinical study done on BR and exercise.  Based on this clinical study, while working out at the same workload (done on a stationary bike ergometer), you can perform the same workload at the HR 2 or 3 beats per minutes less wearing BR.  I introduced this product to some of the top elite Japanese marathon runners but I was careful about telling them that this does NOT mean they could run faster.  Running faster, or better, involves a lot more than just slightly lower HR.  Running economy, yes; you can probably measure it with HR.  But you can't say you can run better or perform better with it (not that you're saying it).  Not that you're necessarily insinuating it but your example of running London Marathon in 3:15 in one type of shoes and 3 weeks later another marathon in 3:07 in another type of shoes is not a good comparison at all.  Chances are; you probably would have run almost equivalent in the same shoes anyway.  Whether it's 3:07 or 3:09 we'd never know.  Who knows; you might have run 3:05 in the same shoes??? (doubt it...)  My point is; that the reason for your improvement is most probably not SOLELY due to the lighter shoes.  It would have been an interesting case study if you had one more example of even lighter shoes--something like Musha or Piranha or...I don't know if they make those super thin racing shoes any more but New Balance racing shoes that Lidia Simon used to always wear.

              Do you wear socks?

               

              If you do, take them off.  That would make you lighter too. 

               

              Now if you start shaving off body hair, that might be too extreme.

               

              I actually ran without socks whenever I raced in college.  After my first steeplechase, my socks sucked up too much water and made me feel real heavy.  Next steeple I didn't wear socks.  I liked how it felt wearing my track spikes without socks so I stopped wearing socks for races all together.  

              You wore socks to run steeplechase????  What were you thinking!!? ;o)

                The next logical experiment would be to run 1.8% faster with the lighter shoes and compare average heart rates.

                 Well, I did pretty much what you suggested this evening. The results are here:

                http://christofschwiening.blogspot.co.uk/2012/05/quantification-of-reduction-in-effort_29.html

                Excellent suggestion!

                  An interesting study and I'll totally agree with the concept.

                   

                  Not that you're necessarily insinuating it but your example of running London Marathon in 3:15 in one type of shoes and 3 weeks later another marathon in 3:07 in another type of shoes is not a good comparison at all.  Chances are; you probably would have run almost equivalent in the same shoes anyway.  Whether it's 3:07 or 3:09 we'd never know.  Who knows; you might have run 3:05 in the same shoes??? (doubt it...)  My point is; that the reason for your improvement is most probably not SOLELY due to the lighter shoes.  It would have been an interesting case study if you had one more example of even lighter shoes--something like Musha or Piranha or...I don't know if they make those super thin racing shoes any more but New Balance racing shoes that Lidia Simon used to always wear.

                   Thanks, it is nice to hear that someone is interested! My 3:15 London time was rubbish for several reasons - the first was that I developed a pain in my left thigh at the very start which made me worried and possibly contributed to a very slow first half. The second problem was 3 mins on the loo just over half way. The third was shooting out of the loo at high speed causing a horrible acidosis. If those things had not had happened I think I would have got at least a 3:12 - but, who knows....we need a time machine! But, I am convinced that losing 300g from my feet has a measurable effect on the work I have to do. I want to try loading my Hyperspeeds up with weights so they match the ProGrids. I also want to try the run barefoot since that will shed about the same again. But, I think I will need to sweep the course first and perhaps toughen-up my feet. I suspect that sweeping 1 km of tarmac will take a while.....

                    I have made a very quick stab at reviewing the literature on the subject of running speed and shoe weights. I have tried to include links to the origninal work where possible. I still need to add a conclusion. But, here it is:

                    http://christofschwiening.blogspot.co.uk/2012/05/shoe-weight-and-running-speed.html

                    DoppleBock


                      I really want to wear light weight trainers for my 24 hour race  ~ But I have not run more than 15 miles in them and I am afraid at the damage I will do in the 1st 14-15 hours may impact my last 9-10 hours.  I may bring them along and change into them late in the race.

                      Long dead ... But my stench lingers !

                       

                       

                        As you say in your blog - there is going to be pain! Good luck, and let us know what happens. Never having run more than a couple of marathons a week I have the deepest of respects for 24 hour runners - heroic stuff.

                        bhearn


                          FWIW I ran my first 100 in racing flats. But 100 ≠ 150... totally different world, I imagine.

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