The following Mark's Daily Apple article was written by Mark Sisson, and is narrated by Tina Lehman.

Eleven physical challenges to take this month. Some people don't need any help finding physical challenges.

They naturally and intuitively figure out ways to engage physically with the world and test their prowess.

But that's not everyone, or else we'd see people sprinting down the street, hurtling park benches,

climbing flagpoles, and swinging from tree branch

to tree branch.

It would be a cool world to be sure.

It's just not the one we live in.

In this world, where physical challenges are usually optional, we have to go looking for them.

What are some fitness challenges to try?

I've got 11. Number 1. Climb a tree tall enough to make you a little queasy.

How high you go depends on the climbers, faculties, and experience.

Don't underestimate yourself on this one, however.

This one, of course, tests both psychological and physical fitness.

Everyone has that point where they begin questioning the decision to climb.

And climbing itself requires hand-eye coordination, tactical planning, and physical strength.

Compared to bouldering, climbing a tree is much more user-friendly, allowing the climber to dictate the terms of ascent.

You can rest in between branches or go full steam ahead.

You can get winded or take long rest periods in between bouts of exertion.

Try different routes up and back.

Practice until you can ascend and descend smoothly.

Do pull-ups and dips on the branches.

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