Me personally, I run 4 miles and on the there are various hills which I sprint up and down so many times depending on there height and steepness.

On the root I run up plenty of hills, and on teh flats I run at a pace barely faster than Jogging, after about 2 miles I come to the hill area of the run. The steepest hill is about a quater or a mile so I don't sprint it, I just run it as fast as I can (jogging, sprinting and running are different, theres more to it than just speed ) up and down three times. then I get to a steeper hill, but its only about 10 meters, I sprint that one at full out speed 5 times up and down before jogging the 2 odd miles back home.

You can rust fast for a minute, but you can't sprint full out for a minute unless your super man

I hate to say it aswell, most of the guys you listed are either light, coloured or both. With out trying to offend any one, alot of coloured people have 'chicken legs'...

Look at Jeff Lacy, massive upper body, tiny legs.