A player who sheltered through a two-hour lightning delay comes back jumping 3.5 percent lower and sprinting up to 1.8 percent slower, and only a plyometric re-warm-up matched to his idle time pulls those numbers back.

Staff need the reset rule, a log of each player’s last hard effort, a re-warm-up matched to the gap, and a separate plan for substitutes who never played. The existing weather rules tell officials when play can resume. The existing research tells physiologists what passive waiting does to a player’s legs. Neither document connects the two. Staff have to read the reset clock and then put each player through the re-warm-up his idle time calls for.