Kerr didn't draw names from a hat or use a coach's intuition in deciding his key players needed a break. He used information gathered from wearable technology, the next frontier in the NBA's rapidly accelerating analytics movement.
On the heels of a six-game, nine-day road trip, players were reporting that they were starting to feel worn down. Golden State's director of athletic performance, Keke Lyles, has players fill out a questionnaire every morning to measure soreness, fatigue, sleep quality and other factors that are so important to recovery and injury prevention.
In addition to the red flags on the players' questionnaires, the data Lyles had been collecting all season using the NBA's SportVu cameras in games and wearable technology from Catapult Sports in practice confirmed his fears.
We felt like all those guys were reaching their limits, Lyles said.
With player movement captured at 25 frames per second during games with SportVu cameras, teams can monitor players' movement intensity and acceleration and spot drop-offs that might indicate fatigue and overuse. Layering that in-game data with metrics from a biomechanical movement device that the players wear in practice, Lyles reported to Kerr that it was time to take action.
A lot of non-contact injuries are fatigue-related, Lyles said. If we see big drops consistently over the last few games, and we know in practice they've dropped and they're telling us they're tired and sore and beat up, then we start painting a big picture: Yeah, these guys are probably fatigued.' When they're fatigued, they're at a higher risk.