Some in the NBA think of it the NBA’s silent scourge, reports ESPN.

Still, despite the league’s best efforts — lengthening its schedule in recent years, reducing back-to-backs for five straight seasons (down to an average of 12.4 per team in the coming season), eliminating four-in-five stretches, reducing the nationally televised games that tip off at 10:30 p.m. ET, creating more rest days — sleep deprivation remains what one high-ranking league source intimately involved with player health calls “our biggest issue without a solution.”