At 'only' 5'8" and cycled everywhere in my youth on heavy all-steel bikes, I had what I called 'Earl Campbell thighs' -- You older guys will catch the reference. VERY strong legs. I could do reps of the entire weight stack on the leg press (~760 lbs) on the Nautilus weight machine in high school.. My vertical leap? With a running start I could reach the basketball rim with the middle of my hand (not enough to dunk, though) I was also a long jumper in Track... I had LOTS of spring in my legs!!!

None of that leaping ability helped with my cycling though. Even at 18 yrs of age, I used to be whooped after only 10 miles or so. Only through riding more and more was I able to build any endurance or speed. A year later? 60 miles was a 'normal' afternoon ride... Centuries were sub- six hours - counting breaks!