This URL is brief & says plenty; check it out: http://www.scientificamerican.com/blog/post.cfm?id=running-barefoot-is-better-research-2010-01-27Especially watch the video; Very clear
Yes there is less pressure on the knees of people who run on their fore foot, or at least strike there 1st. The problem arises for most runners however if they do not follow this with the heel at least lightly “kissing” the surface as the great 800m runner, Sebastian Coe puts it.Remember that a number of elite athletes do run on their forefeet, in shoes, as they were born to run. I am a plodder & run on my forefeet for heaven’s sake. A highly supportive shoe kills me, but even though I teach biomechanical drills, can demonstrate most forms of running, spend my entire childhood & much of my adult life barefoot, I cannot & would not run barefoot on asphalt – I never run on concrete; I rather run through shrubbery! And my goodness, how unnatural, I wear gloves, as this wussy South African could never finish a 30 minute session in a Boulder winter without them! My genetically given foot structure is that of a high arch with zero ability to pronate (natures natural shock absorber & foot spring). I need protection & some cushioning.Not all heel strikers are equal either – remember the heel is far closer to the body’s dynamic center of mass than the forefoot & therefore promotes a partial passing strike of the surface, allowing the body to be somewhat more upright. This landing under the body, instead of ahead of it, is a very good thing & leads to a rolling, efficient way to run. This is also a rotational force & deflects & loads quite effectively. The foot serves as a partial wheel & rolls smoothly from heel to toe. Poor heel striking, with the shin angled backward & the heel striking the ground way ahead of the center of mass, with the toe up high & the shin working like the dickens to decelerate the inevitable slap down & inward that is to follow is a sure way to entice every running injury in the book. This happens because these runners are truly mimicking walking (& how most everyday runners learned to run) – they are simply launching & dropping onto the ground in a display of aerial power walking. This comes from a lack of background in running & these individuals (the majority) have progressed their natural walk to a launched version & call it running. Of course it is unnatural, has damaging peak forces & without highly protective footwear will injure them. Again, I am all for education & returning our nutrition, etc to a simpler way, but at the rate at which safe healthy information gets to the majority of the community that requires it, we will create more problems than we solve if we allow every runner & prospective runner to hurl themselves into BFR. A well designed study done at the University of Cape Town Sports Science Institute, under the auspices of the world renowned scientist & author of what is commonly acknowledged greatest running book ever written, Dr. Tim Noakes produced interesting results. The instigator was a Dr. Nicolas Romanov, he of the POSE method fame or infamy, depending where you seat yourself. He says also that we should ALL run on our forefoot. Now similar to these other studies done on BFR, this study found decreased pressure in the knee joint & supported Dr. Romanov’s notions. Anecdotally however almost every individual in the study developed achilles tendon problems soon after the study completion. Dr. Romanov says the transition may have been too rapid. Add to this of course that there was no footwear intervention either, but I surmise that this is the biggest issue that will arise if we have a mass exodus of runners over to being savannah plains runners on the paved & cobbled streets of the world – a huge increase in achilles tendon & similar injuries.I believe I have 2 more of these (BFR blogs) in me: One on footwear that might meet the biomechanical requirements of BFR & no, not minimalist in the least, & how to transition from shod to some BFR without irreparably dinging yourself.Till then, take care, be your swiftest & have a blast.