MIS's Tough Mudder event is being replaced by a similar mud-filled obstacle course in 2017 - the Spartan Race. Spartan Races emphasize competition, whereas Tough Mudders stress teamwork.

May 8, 2014— -- Despite their hefty price tags and reports of bloody diarrhea and even deaths, obstacle races like Spartan Race, Tough Mudder and Warrior Dash are seeing a surge in popularity ...

Photo: Spartan Race. Locations. Tough Mudder: The company had 28 events in 2012 and now has more than 50 scheduled for 2013, across North America and in Europe, Asia, South Africa, and Australia.

Keneally explained that while the Tough Mudder and Spartan Race might seem interchangeable to naive outsiders, they’re incredibly different experiences with different principles.

Soft times call for extreme racing.