The act of choosing the most direct route down a mountain - not on the set trail - then proceeding to run down it at high speeds.

*It is an extremely dangerous practice that should only be performed by trained professionals and may result in serious injury or death.

The concept is simple:
Get yourself to the peak of a mountain by any means necessary, throw all caution to the wind, and hurtle yourself down the mountain like you have nothing to lose (when in reality you have everything to lose). Your insanity will either bring you feelings of accomplishment and exhileration, or feelings of throbbing legs, gasping for breath, and pain in various regions of the body.

100% chance of catching a well earned case of "Potty Mouth"

Invetned at the peak of Mayflower Gulch, Summit County, Colorado on August 12, 2010. When two hikers realized they had only 10 minutes to reach the meadow below where their family was waiting, they had to improvise. It took them 45 minutes to hike to the summit...they made it down in 9 minutes and 20 seconds.
Hiker A: "Oh s#;t! We only have 10 minutes to get down this mountain!"
Hiker B: "Looks like it's time for some Mountain Running!"

When one is in need of reaching the base of a mountain in an unreasonably short amount of time, it may become necessary to take part in Mountain Running.
by B-Stan:Pridge-Bizkit August 15, 2010
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A phrase that is often used interchangebly with touge.
often meaning mountain racing or driving

verb
Racer A-hey I just got my car fixed.
Racer B-are you up for doing some on mountain running?
Racer A}-why not
by specracer29 April 28, 2008
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Shitting your tent so vad you have to leave it behind at a music festival after eating bad shrooms.
Must have been the fried oyster -mountain runs

Little kid: Hey daddy, whats a mountain runs?
Dad: I think its refered to as a stowers.
by Mountainruns365 October 10, 2013
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