Football players, by the mere definition of their sport, thrive on hitting people.

Except for a select number of kickers, punters and happy-footed quarterbacks, these athletes crave contact, conflict and competition.

They just can’t live without it.

So if you’re one of these specimens, who are you supposed to hit while in the wilds of spring practice, with nary an opposing team’s helmet or jersey to be found?

Your teammates, of course.

“It makes practice a little more fun,” Northwestern coach Pat Fitzgerald said. “It’s amazing how quick practice goes when you compete your tail off.”

Fitzgerald said the team will have plenty of time to come together before the season starts in September.

But until then, it’s important for his players to stay sharp by whaling on each other.

So it’s not terribly surprising to see defensive end Corey Wootton and tackle Dylan Thiry at each other’s throats at the end of a trench drill, only to see them huddled together at the end of the field just minutes later, listening to Fitzgerald talk about playing Wildcat football.

And all this latent aggression has to be encouraging for a team that continually lost the “six-inch war” last year, a series of limited skirmishes predicated almost solely on pure physicality.

On a weekly basis last year, NU was pushed around by larger, more physical fronts. Opposing teams’ defensive lines seemed just a step too quick for the Cats’ offensive front. Opposing teams’ offensive lines seemed about a foot too wide for NU’s blitzers.

A prime example of this was the 41-9 loss to Wisconsin in October. The Badgers’ offensive line, tall as corn stalks and wide as the Midwestern horizon, created gigantic holes for halfback P.J. Hill, no debutante himself at more than 240 pounds.

But by the looks of some of its practice sessions, this team won’t be so easily pushed around.

Wooton is 6 feet 7, 275 pounds … and still growing. When he and the 6-foot-8 Thiry faced off in Tuesday’s practice, there was more than 13 feet and almost 700 pounds of man rocking the earth with each step.

The offense has even set up a reward system based on physical play.

Although offensive coordinator Garrick McGee declined to comment on the specifics, running back Tyrell Sutton said it involves heavyweight belts and photoshopping.

Throw a devastating pancake block on a blitzing linebacker, get a flyer made with your head grafted onto Hollywood Hulk Hogan’s body.

Turn a 10-yard loss into a three-yard gain, get a shiny belt to carry around campus.

“(McGee’s) making sure everyone on offense is competing with one another,” Sutton said.

Sutton said players get awards in a variety of categories, including the most violent shove on a defensive player.

But the true crown jewel harkens back to mid-1990s vintage professional wrestling lore: the “NWO” award, won for playing Northwestern offense.

Sutton said he has two or three belts and he’s proud of them.

“It’s making us more competitive, to see who can go out and get the most belts,” he said.

“As trivial as it sounds, it’s working.”

A handful of the Cats’ recruits for next season got to see first-hand Tuesday what’s in store for them when they’re eligible to begin practicing with the team.

Defenders laying mammoth hits on running backs and standing over their fallen bodies, screaming. Offensive linemen finishing blocks almost to the point of excess, driving players into the ground and pinning them. Fitzgerald energetically signalling touchdown after an end around by Sidney Stewart, springed from a block on the edge.

Hammering through drills with all the intensity of a regular-season game.

“(Recruits) are able to watch practice and the way we go about things,” Fitzgerald said. “And get punched right between the eyes by the reality of college football.”

The Fitzgerald-mandated 5 a.m. wake-up calls and spring practices spanning nearly three hours before most of the campus is even awake have the Cats thirsting for blood.

They can only hope that this feeling carries over to when they have someone to hit besides themselves.