how can you compare these things? whats the definition of intelligence for you? i think american football or real football (doesn't really matter which one you mean) players have a much higher playing intelligence than freeskiers. on the other hand of course skiers or gymnasts have a much higher body awareness...so whats your point? you think that it needs a higher IQ or more nerve connections or however you want to measure intelligence to perform skiing? i think in every sport the top athletes are close to their maximum of ability, but that has nothing to do with intelligence. the limit of the tricks in skiing for example is in my opinion the physics, so on the moon with lower gravity it wouldn't be too hard to perform 5 flips or whatever...i don't think the brain is the limit there.
hope you'll get my point and understand my english.