People say calf strength and feet strength only account for 10% of speed/vertical.... that seems a bit too low. I'd say it is closer to 15-18%, especially if you have a strong feet and big toe.
A few questions:
-15%? or 18%? Is it the same? why is 15-18 an ok range and 10-15 a not ok one?
-Is that contribution to speed? To vert? To both?
-What is 'speed' that this 15-18 contribution will be? acceleration? top speed? 20yd dash? 40yd dash? 60m? 100m? 200m? all?
-What is 'vert' that this 15-18 contribution will be? SVJ? dropstep? RVJ? single legged? double legged? all?
-What is feet strength? What is calf strength? Why are we mentioning them together, are they bounded?
-What is 'strong feet and big toe' and why does that raise the contribution percentage?
-To whom does that apply? Ectomorphs? Mesomorphs? Bouncy people? Slow people? ? long legged? short legged? Everyone?
I can go on but you get the point...
