Fox's blistering pace allows him to zoom by defenders and create golden opportunities for himself and his teammates, and he's not shy about his most notable attribute.

The 21-year-old Sacramento Kings point guard is using his blinding speed to devastating effect this season. He's one of just four NBA players currently averaging at least 17.5 points, 7 assists and 1.5 steals per game. The other three are Russell Westbrook, James Harden and Jrue Holiday.

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De'Aaron Fox is basketball's Usain Bolt.

The 21-year-old Sacramento Kings point guard is using his blinding speed to devastating effect this season. He's one of just four NBA players currently averaging at least 17.5 points, 7 assists and 1.5 steals per game. The other three are Russell Westbrook, James Harden and Jrue Holiday.

Fox's blistering pace allows him to zoom by defenders and create golden opportunities for himself and his teammates, and he's not shy about his most notable attribute.

"I'm the fastest person in the league," Fox said on Posted Up with Chris Haynes: A Yahoo Sports Podcast. "I be watching film and I be looking at my feet and I be like, 'Man, there's no way people think I'm not the fastest person.'" With the freakish Fox at the helm, the Kings are on pace to win 40+ games for the first time since 2006.

To find out how Fox built his Ferrari-like speed, STACK caught up with Robert Harris, head strength and conditioning coach for Kentucky men's basketball. While Fox had plenty of speed in high school, he took things to another level in college.

Fox arrived at the University of Kentucky in early June of 2016. That gave Harris roughly five months to mold him before the team's first game of the season.

The first thing Kentucky does with all incoming players is administer a test called Functional Movement Screening. Physical therapist Gray Cook, who invented FMS, says it helps "determine the greatest areas of movement deficiency" in an athlete. Fox performed remarkably well in the FMS, demonstrating mobility and movement efficiency rare for athletes his age—especially basketball players.

RELATED: Find Your Weaknesses in Just 10 Minutes With The Functional Movement Screening

"Guys who play basketball on the AAU circuit [like Fox did]—normally, they come in and their body has [many] different kind of deficiencies and things of that nature. His body was in really good shape—the way he moved and his mobility and his flexibility were awesome. The first day of us doing training—from a movement standpoint—you could just tell it was natural [for him]," Harris says.

Some of Fox's speed is natural, no doubt. Certain people are just more fleet-footed than others. But Fox is also stronger than his frame might indicate—especially in his lower half. He measured in at 6-foot-2, 170 pounds at the NBA Draft Combine, and scouting reports referred to him as having a "wiry frame" with "spindly legs." But according to Harris, he possesses "one of the more impressive [amounts of] lower-body strength" he's seen in players of Fox's build. That lower-body strength is a big reason why Fox can make other players look like they're moving underwater; it allows him to create a tremendous amount of ground force as he gallops around the court.

When Harris saw how fast Fox was, he knew no one in college basketball could keep up with the explosive point guard. "I always told him that he could get in the [Kentucky] Derby with the thoroughbreds and finish in the top three," Harris says. However, Fox had the potential to get even faster. He was so used to running with a basketball in his hands that his sprinting mechanics were out of whack. He actually appeared to move slower without the ball by his side. Harris knew that if he could fix Fox's sprinting mechanics, it would help him develop even more speed.

"In order for him to work on his speed and get faster, [he had] to run fast," Harris says. "When he was able to learn how to run without the ball, it made him moving with the ball that much better. It took him to a different level."

Once Harris knew what kind of athlete he had in Fox, he drew up a plan of attack for the weight room. The goal was to continue to build up the fast-twitch muscle fibers that make Fox so explosive while also strengthening his posterior chain—i.e., the muscles on the backside of his body, particularly his hamstrings, glutes and lower back. Many modern athletes are anterior dominant, meaning the muscles on the front of their bodies are significantly stronger than the ones in the back. This condition can be a serious deadweight on performance.

"All of our guys have different training programs. For him, it was all about tapping into those fast-twitch muscle fibers and getting the best out of him. A lot of his work was Clean Pulls, Olympic-style variations—everything to keep him explosive," Harris says. "Then working on the posterior chain. We did a lot of Glute Ham Exercises with him, a lot of exercises more for the backside of his body—hamstrings, glutes, calves, lower back, etc. That kept him stronger on the backside of his body and allowed him to apply more force into the ground when he's running, sprinting or moving laterally."

Fox accepted the challenge and ran with it. Harris has seen few freshmen work harder inside the weight room. He says, "[Fox] works his butt off. He's a grinder."

His ferocious work ethic led Fox to gain five pounds of muscle during his first three weeks on campus. By the time the regular season rolled around, he was ready for war. He was undeniably impressive during an early-season game against Arizona State, posting a 14-point, 11-rebound, 10-assist triple double.

However, Calipari wanted Fox to play even faster. Calipari—undisputedly one of the greatest college basketball coaches in history—knew his freshman point guard would always be the fastest player on the floor regardless of the opponent. Using that speed on a consistent basis was key for Fox if he wanted to overwhelm opponents. After a 96-73 win over Hofstra on Dec. 11, Calipari said Fox "didn't play with the speed we want him to all the time." Fox responded in Kentucky's next game, a nail-biter of a victory over UNC. He posted 24 points, 10 assists, 4 rebounds and 2 steals in the win. "They can't guard [Fox] when [he] goes by. So he's got a lot to learn, but he is special. De'Aaron Fox is special," Calipari said.

The deeper UK went into the season, the sharper Fox seemed to get. One reason was that he approached the training room with the same consistency and attitude he brought to the weight room. "He's definitely a guy who understands the importance of recovery," Harris says. "A lot of guys shy away from the training room, thinking that's where the injured guys go. The training room is also where you go to prevent injuries—they've got Normatec boots, hot tubs, cold tubs, ice, stretching tables. He utilized all of that, and it showed in how his body held up throughout the year. He was constantly going into the lane, taking hits, banging with bigger guys and not missing a beat."

The greatest performance of Fox's collegiate career came in the Wildcats' Sweet 16 matchup against UCLA. Fox dropped 39 points—an NCAA tournament record for a freshman—and thoroughly outplayed Lonzo Ball in Kentucky's 86-75 victory. His dizzying speed and quickness kept the Bruins off balance all night:

Fox's phenomenal freshman season at UK led the Kings to select him with the fifth overall pick in the 2017 NBA Draft. While he flashed his game-breaking speed throughout his rookie campaign, it took time to adjust to the physicality and strength of the NBA game. After all, he couldn't legally enter a bar until less than a month ago.

But Fox lived in the weight room over the summer, adding more than 10 pounds of muscle to his still-maturing frame. The increased strength and size has allowed him to wield his speed more effectively than ever, as he's now capable of destructing a defense in a myriad of ways.

Photo Credit: Andy Lyons/Getty Images, Michael Hickey/Getty Images, Rocky Widner/Getty Images

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