I read a story once about a ritual that was performed by some South
American Indian tribes. Basically, there was a contest where two men
would have to climb to the top of a tall temple. The person who tried
to climb straight up would become tired quickly. The other competitor,
who zig-zagged while he climbed the temple, did not become worn out.
This competitor won.

My memory is a little fuzzy -- I'd like to find out more about this.
Any information pertaining to the ritual would be useful.

This sounds like a "motivational story" used in various training programs.

It does sound like a motivational story. It's the sort of thing people
forward to your inbox. Still, it could be based on some element of
truth.

   Also, just as a curiosity, it sounds somewhat like the analogy
Richard Feynman used to explain the refraction of light in terms of
the principle of least time, except that he used the example of the
lifeguard at a beach, needing to minimise the total it takes to reach
a swimmer in distress.