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Running Economy (Read 1345 times)


Interval Junkie --Nobby

    "Relatively well-studied aspects of form include foot strike position and stride length. Despite some barefoot running advocates' claims that forefoot striking is inherently more economical than rearfoot striking, this wasn't true in Lieberman's most recent study. Lieberman et al. raise the possibility that forefoot striking permits greater elastic energy recovery through the Achilles tendon but also requires more calf muscle activity to control the landing of the foot, thus offering no net advantage over rearfoot striking.

     

    "Stride length and stride frequency have also been researched in some detail. (The two are inversely related; if your pace is held constant, you must decrease your stride length to increase your stride frequency and vice versa.) In the early 1980s, Cavanagh and Williams found that, when subjects tried several different stride lengths, their RE was best around the stride length that they used naturally. "There is zero evidence that overstriding is rampant," says an almost-strident Kram. "The myth of 'increase your stride rate, become more economical' is bunk." Presumably Kram isn't referring to the small percentage of runners who exhibit genuine overstriding and can be given feedback to improve RE, as reported in a 1994 Journal of Applied Physiology paper by Don Morgan and colleagues at the University of North Carolina at Greensboro."

     

    Above from Running Times article. (bold mine)

     

    Thought the above was interesting, considering how prevelant both forefoot and stride-rates are in the available literature (aka the Web, and other sources of questionable authority).

     

    Of course, saying stride-rate and forefoot strike doesn't affect RE, is not the same as saying they don't prevent injury or make you faster.

    2014 Goals:  sub-3 Marathon 

    Current Status 08/28: Slowly working back up from a pelvic stress fracture.  4mil distance PR w00t!


    Feeling the growl again

      Define what "stride length used naturally" is.  Years ago before I got into high-mileage training I used a substantially longer stride.  Once I started into high mileage I noticed that, over time, I shortened my stride...presumably as my body learned to be more economical under the pressure of the volume of training I did.

       

      I can see how using an "unnatural"-feeling stride would be inherently inefficient as you are forcing something, but what is natural one day may not be what is natural months/years later after you have trained to make it...well, natural.  In other words, some experiment that tests someone's efficiency at different stride lengths at a single point in time will of course say whatever is natural is most efficient at that time.  But that doesn't mean something else may be better in the long term.

       

      If people get worked up over this I'd suggest not to worry about it and just run more.  Wink

      "If you want to be a bad a$s, then do what a bad a$s does.  There's your pep talk for today.  Go Run." -- Slo_Hand

       

        If people get worked up over this I'd suggest not to worry about it and just run more.  Wink

         

        You know Spaniel - this single statement can probably be used to answer 90% of all the questions ever asked about running.....

         

        "Don't worry about it and just run more".....

         

        'least that's what I think

        Champions are made when no one is watching

           

          If people get worked up over this I'd suggest not to worry about it and just run more.  Wink

           

          True dat. The more I run, the more this stuff just sorts itself out. My stride has gotten shorter because that's my happy place at 60 mpw. 

            Some pretty cool pictures were taken of the footstrike of the men's and women's runners in the 10k field at the Olympic Trials this weekend. You can see them below. I think it's pretty safe to assume that these are efficient runners. As these pictures make very clear, footstrike is widely variable among these runners. I think this suggests that changing one's footstrike intentionally in the hope that one might become more efficient is a fool's errand.

             

            I agree that the body seems to fall into a naturally efficient stride over time, but I would say also that it is important to run a variety of paces and over a variety of terrains, perhaps especially early in the runner's career. My unscientific opinion is that we are capable of developing a wide variety of footstrikes that vary according to pace, terrain, and levels of fatigue. We should avoid reductive "either-ors" in this area and in many other areas.

             

             

              I thought this thread was about my family?

              And you can quote me as saying I was mis-quoted. Groucho Marx

               

              Rob

                I thought this thread was about my family?

                 

                Do folks refer to your family as "The Economists?"

                  Do folks refer to your family as "The Economists?"

                   

                  Not as far as you know...

                  And you can quote me as saying I was mis-quoted. Groucho Marx

                   

                  Rob

                    hard to know for sure by the quick one snapshot of those runners striking but it almost looks to me that there are  about an even # forefoot strikers as there are heel strikers.  and a few flat foot strikers as well

                    xor


                      What kind of things rob economy?

                       


                      HobbyJogger & HobbyRacer

                        What kind of things rob economy?

                         

                        Having your shoe come untied.

                         

                        Hitting a hurdle.

                         

                        Hitting a runner in front of you and going down.

                        It's a 5k. It hurt like hell...then I tried to pick it up. The end.


                        Feeling the growl again

                          Having your shoe come untied.

                           

                          Hitting a hurdle.

                           

                          Hitting a runner in front of you and going down.

                           

                          A talent bubble bursting

                          "If you want to be a bad a$s, then do what a bad a$s does.  There's your pep talk for today.  Go Run." -- Slo_Hand

                           

                            Bankers?

                             

                              Low tire pressure. A dirty air filter.

                              Runners run.

                              JimR


                                offshore manufacturing

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