Could the key to better endurance be BEET JUICE!??!

Only up to a point.

Recommended dosage:

Eight ounces (two juiced beets) three times a week. Blend with eight ounces of sweeter fruit juices, like apple, carrot, or tangerine, to improve the taste.

Isn't antioxidant just a fancy word for vitamin?

And isn't electrolyte just fancy word for salt?

Yes, but electrolytes are what plants crave.

there are other things to juice which give you the same or more/better nutrition and which do NOT stain my damn juicer pink! /wishing-i-knew-then-what-i-know-now-lol

All the Olympic athletes are drinking beet juice: http://gawker.com/5929716/all-the-olympic-athletes-are-guzzling-beet-juice