Either you are one of those people who signs up for Tough Mudder/Cross-Fit - the weekend pursuit over concrete obstacle courses, through barbed wire, electrical cables and six feet of mud - or you're not. Tens of thousands of people in the Australia take part in these events every year and it has quickly overtaken marathon running, and gym training as THE mass-participation event that people of all abilities aspire to take part in. You have to be quick though as events sell out within hours.

DANIEL KUNITZ is the Editor-in-Chief of Modern Painters, former editor of The Paris Review and Details, and a contributor to Vanity Fair, Harper's and New York Magazine. He is also an exercise fanatic who spends his weekends competing in grueling fitness challenges. He lives in New York.

Either you are one of those people who signs up for Tough Mudder/Cross-Fit - the weekend pursuit over concrete obstacle courses, through barbed wire, electrical cables and six feet of mud - or you're not. Tens of thousands of people in the Australia take part in these events every year and it has quickly overtaken marathon running, and gym training as THE mass-participation event that people of all abilities aspire to take part in. You have to be quick though as events sell out within hours.

DANIEL KUNITZ is the Editor-in-Chief of Modern Painters, former editor of The Paris Review and Details, and a contributor to Vanity Fair, Harper's and New York Magazine. He is also an exercise fanatic who spends his weekends competing in grueling fitness challenges. He lives in New York.