"He excelled in baseball and especially in football," Zack's dad Victor said.
After a hard hit to the head in a middle school football game last fall, Zack came off the field, but the 13-year-old linebacker went back in during the second half.
Then he collapsed, CBS News correspondent Sandra Hughes reports.
"I was begging God to keep him alive," Victor Lystedt said. "He was in a coma for over 30 days."
Now, Dad is still coaching, but it's a whole new ball game. Zack can't speak.
He can't walk. He can't even swallow. His mom quit her job as a dental assistant near Seattle to take care of him.
Zack's parents say he never should have been allowed back into the game after the first serious hit on the head.
"Because one game isn't worth a lifetime of events that we have to endure," Victor Lystedt said.
A lawyer for the Tahoma school district says Zack showed no signs of a concussion before resuming play.
Seventeen-year-old Matthew Colby had not fully recovered from a hard hit when he played the following week — a fatal mistake for the Costa Mesa teenager. He walked off the field and collapsed.
"I put my hand on his shoulder and I said, 'Matthew, keep your eyes open,'" his grandfather, Mike Colby said. "And pretty soon he couldn't."
The lesson for young athletes, parents and coaches: you don't need to be "unconscious" for a concussion to be serious.
Any of these symptoms – headaches, dizziness, blurred vision, memory loss, inability to concentrate – require a trip to the doctor before getting back in the game.
Many schools now require athletes to take a pre-season test for comparison if they sustain a head injury later.
"The benefit of it is tremendous, in terms of what we can do with it post-concussion," said Dr. Vernon William of the Sports Concussion Institute. "It's almost a no-brainer."
Zack's parents believe his injury could have been prevented, and will be overcome.
"With his internal drive and spirit and with his warrior attitude, he'll be all right, he'll get through all of this," his dad said.