The reason I started this blog was to stimulate an intelligent dialogue on the issues pertaining to the design and modification of ski equipment and the formulation of ski technique based on sound principles of science. The comment below on BOOT BOARD (ZEPPA) RAMP ANGLE VS. BOOT SIZE was received today from Michael Pupko. I have underlined key statements.
Excellent presentation on boot length and the binding’s effect on net ramp. Anyone that is going to experiment with lowering their ramp angle needs to be aware that they will have to do something about the restriction on ‘ankle glide path,’ and the ability to flex their ankles within the ski boot shaft or they may end up with a false conclusion.
I didn’t have the smarts to start with the fact that the ski boot locks up the ankle and also ‘race fit’ etc. restricts all normal foot function. So my approach to not being able to flex my ankles enough to get out of the back seat was to raise the ramp angle because it does 2 things; first it ‘artificially’ gives the skier more forward lean without using up the limited ankle flex available thus getting them out of the back seat and second, from that position I found I could ‘drop’ into the tongue of the boot using body weight rather than the tiny muscles in the front of the shin that aren’t designed for bending rigid plastic ski boots. As I removed the obstacles to foot function, first by trial and a lot of error on my own and then with the help of this blog in regard to ankle glide path, allowing toe spread, and removing arch impediments I have greatly reduced my ramp down to a third of what it was at its’ literal zenith. The trouble with starting within a boot with too much ramp in the zeppa, one has to really tighten the boot cuff to prevent falling forward out of the boot. This is what David addresses before the skier steps into the bindings and those experimenting with ramp angle must do so also. I originally improved my fore/aft ‘balance’ by increasing the ramp angle but it kept my feet locked up or even increased that issue. Everything has to be fixed where the problem is to get the optimum results; adding oil to the car’s engine won’t help if the gas tank is empty.
I’ve been playing with body position while running this summer. Due to my knee issue, the only way I can run without stressing the knee is to land on the ball of my foot; forefoot strike. Going down hills this has been fine but I started playing with the position of my COM due to a discussion with a friend. I discovered that I was running downhill very much like walking down steps until I lowered my COM and that really smoothed out the foot strikes. What I realized is that in a sense I’m stepping down as if my foot is ramped but adjust it according to the slope and needs. Thus I can see why there needs to be some ramp in the ski equipment for going downhill but the industry has gone way overboard with net ramp and forward lean because someone decided to not bother with allowing natural ankle movement in ski boots. I tried to find my last pair of leather boots to see what was underfoot in them, but unfortunately had no luck. I have noticed for years from seeing old pictures of skiers in leather boots, how they flex normally like other sports. That still didn’t make me figure out that we should do likewise in ‘modern’ plastic ski boots because I believed they were made and fitted by experts that knew what they were doing. Thanks David for helping me get over that misconception!!
- Michael Pupko
In my next post will explain why it is important for ankle flexion to occur within the confines of the boot shaft and how to determine optimal boot shaft angle.