Baseball players are wired up.
Yankees reliever Dellin Betances wears a sleeve around his elbow to measure stress on a ligament. Chris Coghlan spent spring training with the Phillies using a wrist band to check his sleep and recovery. Others have GPS devices hidden under their uniforms.
In 21st-century baseball, digital devices monitor heart rates, skin temperature — they even track fielder's movements, all part of the exponential data explosion used to determine batting orders, pitching changes and defensive shifts.
"I love to compare what the results say to how I really feel," Coghlan said. "After three years of data, I enjoy comparing to see how accurate it is.