It's not just NFL players who have to stay in shape during the offseason. Their coaches are also looking for ways to stay active.

Most NFL coaches, however, probably will not go to as extreme lengths to stay fit as John Harbaugh. Fresh off a victory over his brother's San Francisco 49ers in the Super Bowl, Harbaugh recently completed a Tough Mudder race in Gerrardstown, W.Va.

If you're unfamiliar with these military-inspired obstacle course events, they are normally 10-to-12 miles and include everything from carrying logs to crawling through mud. Invented by a Harvard Business School student, these races have become extremely popular in the past few years.

The course Harbaugh completed was designed by British Special Forces. The 50-year-old Harbaugh, who is know for his intense workouts, wore a shirt that said "Sack Lunch" on the front and "I will" on the back.

The Baltimore Sun reported that Harbaugh did the event with members of the Ravens front office, including senior vice president of public and community relations Kevin Byrne.

Harbaugh looks winded in the video below, but jumping into piles of mud and crawling under barbed wire will do that to you.

This text will be replaced

So, Jim Harbaugh, how are you going to top that?

Related Story: How One Man Planked For Three Hours

Like us on facebook, follow us on twitter, and subscribe to our YouTube channel.

VIDEO OF THE DAY:
Meet The 'Batmobile' Of Food Trucks