So, all my life I've pedaled by simply pressing down on the pedals. I had no idea how any cyclists got big calves or hams from it, only my Glutes and quads were ever sore.

Then recently I'd heard of the concept of spinning versus mashing the pedals. Practiced this yesterday-- I felt like my hams are doing all the work-- what?!? I don't know how to alternate so quickly between using quad and hams on higher cadences for each phase of the stroke, or where the calves even come into play. I want to become a sprint cyclist too, so this must be pretty important! Please kindly lend me a few pointers. Thank you! -Michael