Whats my ratio? Do I have more slow-twitch or fast-twitch muscle fibers? Aside from having a muscle biopsy done, I suppose that determining muscle-fiber composition is a matter of deduction.

The fast-twitch fibers come to the forefront during short, hard bursts of pedaling, such as sprints. During a long ride at a moderate pace, the slow-twitch fibers carry the day.

We all have both types of muscle fibers, in our own unique ratios. Sometimes I wonder which type of fiber is predominant in my own muscles.

When I work at pushing the cadence while in a very hard gear, my legs tire quickly. Does that mean that I have a long way to go in building strength; or does it mean that I don\’t have a lot of fast-twitch fibers? Perhaps both?

On the other hand, a high cadence in a very low gear (as when fighting a 25 mph headwind) leaves my legs feeling heavy and tired. Have I become too much of a masher? I seem to be most comfortable when I can ride the big ring with a medium-large cog; and at a cadence in the 70s. Is that mashing, or is it spinning?

Or does it really  matter whether I have 3:1 slow-twitch : fast-twitch fibers; the other way around; or something entirely different? Running all those numbers through my mind during a ride won\’t make the ride any more fun.

Knowing my exact muscle-fiber composition would be merely satisfying my curiosity. I\’d probably go right back to riding the same way I\’ve been riding; but at least I\’d know: what\’s my ratio.