Driveline Pro Day
Charles King had always had an interest in biomechanics, dating back to his TCU days when he would go online to read the Driveline blog and use PlyoCare Balls in an effort to shorten his arm action, a la Joe Kelly.
After five years pitching for the Horned Frogs, King decided to go work in professional baseball. Not as a player, but in the San Diego Padres’ sports science department.
The itch to pitch was still there, though. And he was still reading the Driveline blog. Once or twice a week he would hop up onto the mound and throw four or five pitches, just to sort of see for himself if any of the reading he had been doing would translate to throwing.
King quit his job with the Padres to give pitching another shot. The thing was, he knew he could only go so far with his self-coaching tactics.
“I got to a point where I wasn’t going to make any more headway doing what I was doing and I needed to go somewhere where they could give me something objective to work on,” he said.
What better place to train than the place you had been studying for years?
King came to Driveline to motion capture in October of 2023. That motion capture confirmed some things for him (he throws really hard), and surprised him in other ways. He had been told his whole life that his arm action left a lot to be desired, but the motion capture showed it in the 99th percentile.
The biggest area of improvement for King was his hip-shoulder separation, which he was completely unaware of. It was in the seventh percentile. So he went to work on gaining some range of motion, and in four months, he had gained 15-20 degrees of T-spine motion in both directions.
He never would have found the issue without his initial motion capture.
The timing couldn’t have been any better. By the time King had added that extra zip to his fastball, it was time for Driveline Pro Day.
He showed off his improved heater, a splitter he had added since working at Driveline, and a sweeper that was infinitely better than the slider that had always backed up on him in college.
And then, everything changed. He threw harder than he ever had before, with secondary pitches to compliment the fastball. When he was done, he shook some hands, went to his car to call his parents and his girlfriend, and it started to sink in that he was about to become a professional baseball player.
“I kind of surprised myself a little bit,” King said. “I wasn’t expecting to sit 97, in all honesty. I was hoping to touch 97. So to sit 97 and touch 98 was pretty special…My life essentially changed in 24 hours.”