This is scientific American 60 second science. I'm Christopher and Tagyatta.

Head up to the mountains and if the steep trails don't slow you down, the thin air will.

There's less oxygen up there, so strenuous activity can leave you dizzy, out of breath, or worse.

But even though you're beaten, biochemical processes are already busy at work, acclimating your body.

Scientists investigated those pathways in humans and mice.

They found that exposure to low oxygen

depletes stores of a red blood cell protein.

It's called E-E-N-T-1.

And that's a good thing, because now other substances

that protect your body against low oxygen

are free to rapidly accumulate

and help the body adapt.

But here's the kicker.

Once the E-E-N-TE1 protein goes away, it doesn't come back.

Meaning red blood cells kind of remember their altitude exposure.

And that means if you hit the mountains again soon enough, you can acclimate faster than you did the first time.

The findings are in the journal Nature Communications.

There is one caveat though.

The Red Plus Life lifespan is 120 days.

Study Arthur Yongshaw, a biochemist with the UT Health Science Center in Houston.

The longer you stay at sea level before you re-climb the high altitude, then such a memory

will gradually disappear.

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