CHICAGO (CBS) — Bears running back David Montgomery said his working with the best speed trainer in the world.

As CBS 2’s Matt Zahn reported Thursday night, that trainer is Chris Korfist – a social studies teacher at Hinsdale Central and track coach at Homewood-Flossmoor.

READ MORE: Over 24,000 Unemployment Claims Filed In Illinois Last Week Amid COVID-19 Pandemic

How they connected is pretty simple. What Korfist is doing is a bit more complicated.

“He’s actually teaching me how to run,” Montgomery said.

Added Korfist: “I’ve always been obsessed with learning how to run faster. I’m kind of on a quest, you know, for that magic bullet to make someone faster.”

It’s maybe more science than magic, but Korfist seems to have figured something out. Working out of his own driveway, he’s trained many athletes over the years, consulted for NFL teams, and even designed programs for the Cubs.

It was a former student and trainee that got him connected with Montgomery last summer.

READ MORE: For These Two Standout Students, Their Achievements Speak Volumes

“Thomas Ives is a practice spot player for the Bears, and I’ve trained him since high school ¬- sophomore year (at Hinsdale Central High School). He was roommates with David, and David said: ‘You know, everyone tells me I’m slow. I’m not slow. I had a bad 40.’ And Thomas said, ‘Well, I know this guy,’ just like we say here in Chicago,” Korfist said. “Next thing I know, I see Thomas walking down my driveway with another guy. They come to my garage door. ‘Hi, I’m David Montgomery, running back for the Bears.’ Oh, interesting. This will be interesting.”

It didn’t take long for Korfist to get to work improving Montgomery.

“We look for power leaks,” he explained “David had a pelvis – he’s so strong that when he pushed with his run, his pelvis actually rocked backwards. His foot hitting the ground became a brake rather than an accelerator.”

To simplify it, Korfist’s machine pulls you faster than you think you can go – and basically forces your body to get into the perfect running position. For Montgomery, it took only two sessions to figure it out.

“Last year, we saw an increase of about 1.2 miles per hour, which in football is quite a bit,” Korfist said. “David got by with just being an incredibly powerful athlete. His goal is to be the best running back in the NFL for a number of years.”

Korfist said that Montgomery loves to talk philosophy, but when he flips that switch, nobody goes as hard as he does.

MORE NEWS: 2 Mass Shootings Reported At The Same Time In Chicago Hours After President Biden Announces Plan To Address City's Violence

You can learn more about Korfist’s speed training here.