Originally Posted by carleton

A key indicator is muscle fiber type. Generally, your muscle fiber type percentages does not change over time. So if you were predisposed to being an endurance athlete as a kid, you'll likely be the same as an adult. Same for sprinters.

High school athletics are a good testing ground for muscle fiber time because most schools have the students doing all kinds of sports that involve everything from short bursts of speed (100M dash) to long events (1 mile run). And the sample sizes are relatively large (LOTS of kids in the school doing the same things), so if you are above average in something there, this is good.

If you were in fair shape, your performance, likes, and dislikes of these events will lend a valuable clues to your muscle fiber type percentage. In layman's terms: TALENT

So...

If you were a "sprinter" in high school track and field or were above average in sports that use fast-twitch muscles or lots of power, then you will probably lean towards being better at sprint events because you have a higher percentage of "fast twitch" muscles.

If you were an "long distance" runner in high school track and field (events 1 mile /1,600m or longer) then you will likely be better at endurance events because you have a higher percentage of fatigue-resistance "slow twitch" muscles.

If you were best at "middle distance" events like the 800M or you didn't particularly excel in sprint or long events, then you may be an all-around racer or simply above-average across the board.
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