July 15, 2008
There are a number of ideas of how to prevent injuries – running on trails, weight training, doing long runs slowly, or even incorporating walking breaks (Jeff Galloway‘s perspective). Another perspective is good bio mechanics. There’s a growing trend of running techniques out there: Chi Running, Pose Running, and Evolution Running, all of which have one thing in common: landing on your forefoot/midfoot (aka “ball of the foot”), rather then the heel.
I touched upon running this way when I discussed barefoot running and the Vibram FiveFingers. In either case, the tendency is to land on the ball of the foot, and this enables the “lower-leg spring” to be activated greater. This is the combination of the plantar fascii, achilles tendon, and the calf muscle, which function together to absorb energy upon impact and release it as you take the next step. While this initially causes some soreness while adapting to the new stress in that region, it’s quite clear that it’s better suited for handling the shock forces than the knees and hips, which take more abuse in a heel landing. I think the animation from Newton Running illustrates it best.
After developing my “lower-leg spring” w/ my Vibram FiveFingers, I started to incorporate a forefoot/midfoot strike with my current pair of running shoes. It has not been a seamless transition. I tend to run faster at the beginning of my runs, and slower at then end then I would w/ my normal heel strike. I think this is because the technique does allow me to run faster, but I don’t yet have the necessary muscular endurance in the muscle groups that are greater used. I end up deriving more power from the glutes, for instance. This is potentially a good thing, as the glutes are the biggest muscles in the human body, so I would think it would have more potential for power then pushing w/ the quads.
A strange aspect about the transition is that I’m finding it difficult to accelerate while running on the balls of my feet. When I ran track events in high school on track spikes, I’d run on the balls of my feet, so I’m used to running fast that way. I’m also used to shifting to the balls of my feet when sprinting to the finish of races and training runs. Running fast seemed to come natural in this manner, but accelerating while having run the rest of my run on the balls of my feet seems to be more difficult for some reason. Perhaps, again, this is because I’ve yet to sufficiently develop the necessary localized muscular endurance. Time will tell if I’m able reap the benefits.
June 7, 2008
I’ve been meaning to write this for a while, but I wanted to put a few miles in the Vibram FiveFingers over a period of time and give myself a chance to get used to them before giving them a full review. I’ve also neglected my blog the past month because I’ve been busy with work and had been out of town a couple weekends (congratulations to a certain doctor on her graduation and new apartment!). But alas, here we go:
I felt the biggest difference the first few times I ran in the Vibram FiveFingers KSO (Keep Stuff Out). It was quite a stimulating experience. I felt the ground better then I thought I would (not quite the same as being barefoot, but much closer then I expected). I was naturally inclined to run on the balls of my feet, rather than the heel strike I’ve come accustomed to in my running shoes. This was a great sensation. I felt like I was running on a couple of springs, rather then in shoes. My feet muscles, Achilles tendon, and calf muscles worked together to act as this spring. Of course, the days after my initial runs left these groups sore, like they got a good work out. It also left them stimulated, like I’d learn a new way of doing something.
These initial runs were short, slow, and run on a grassy, mildly hilly course. Typically just 1 mile was enough early on for my feet & calves to feel like they got a good workout. I also didn’t want to chance a foot injury from trying to do too much too soon. I noticed a big difference on hills – powering up them on the balls of my feet is good running form, and something that I’ve worked on, so it came very natural to me. Going downhill felt unnatural. I was more tempted to use my heel here, not necessarily to initially land on them, but to land on the ball of the foot, then slide down onto the heel.
After a couple of weeks on the grassy course, I decided I’d try a mile in them on the W & OD (paved) bike trail. I definitely felt the pavement more, which is one of the advantages of the FiveFingers – you’re more capable of sensing what punishment you’re submitting your feet & legs to. And punishment indeed it was. I wanted to try running more quickly in them, and I couldn’t avoid the temptation of the speed that naturally came with the springiness, so I went at a quick, but not all-out pace and in my offseason form, ran a 6:57. The speed and the hard surface combined to be a much greater shock to my lower legs then any of the runs before, and left my calves & Achilles sore for about a week. That’s a lesson about adjusting to these – start slow, short, and soft, then gradually proceed to longer, faster runs on harder surfaces.
A lot of the sensation and the benefits that come from the FiveFingers could be achieved by running barefoot. You’d get better feedback from your feet, but the trade off is you’d have to develop tougher skin. In the FiveFingers, you don’t need to do this because they act as a tough layer for your feet. Not only do you adapt faster, but you don’t have to worry about the risk of puncturing the skin of your feet with anything sharp.