It's a training regime that is used by those in the military and police tactical units. It focuses on everything from combat to survival, because one of the principles behind it is it doesn't specialize in one particular thing.
It's something that can beat you down if you aren't prepared, or put you among the most elite of athletes once you conquer it.
It's CrossFit, and for Steelers fullback/tight end Will Johnson, it's a way of life now.
Johnson began CrossFit before he signed with the Steelers in an effort to be in the best shape as he was fighting to make an NFL roster, fighting to get the attention of a team after spending his first year out of college not on an NFL roster.
Now, entering his fourth season, not only has Johnson mastered the tenuous CrossFit regime, but he has become a Level 1 instructor, and eventually wants to start his own CrossFit box, where training takes place.
"The NFLPA offered an opportunity for players to learn the business side of CrossFit, as well as earn a Level 1 certification," said Johnson of the offseason program he went through. "We went there for three days and toured different boxes and talked to NFL guys and Dave Castro, who is the creator of the CrossFit Games. I got to learn a little bit more about how to run a box, how to start out. It gives me insight into the future. It's what I want to do in the future, get into CrossFit and open a box. It was fun and exciting."
Johnson has become the face for the workout in the NFL, and is featured on a poster the NFLPA did showing him doing tire flips and jumping over tires. And those tires he flips, they aren't the ones you will find on the car you are driving.
"I flipped an 800 pound tire. It's pretty intense," said Johnson. "They have all kinds of weights. The good thing about CrossFit is it's made for everything and everybody. There is a 50-year old woman in there that could kick my butt. It's tailored for everyone."
Johnson said he would like to do more of the CrossFit training, but it's something he can't always work in with the team's schedule.
"It's still tough because I can't do it as often as I would like during the season," said Johnson. "I am limited to the offseason. I have a good time doing it. I still go back to the same box where I went before the Steelers signed me so that is awesome.
"I want to go back and get my Level 2 certification. That is more the coaching side, how you can interact, watch technique and form of the customers. I now catch myself sitting back and watching guy's technique and form and seeing what coaching points I could give to them. That is all a part of it. It's awesome."