PreSeason Conditioning - 20 in 20

This is a conditioning drill I've used for several years. 20 sets of lines, suicides, horses, or whatever you call them, in 20 minutes. While at Eastern Washington University, we required all of our players to run the 20 in 20 until every one of them made their time individually. At Texas Lutheran, this drill was used as a reward for behavior we deemed to be outside of our expectations.

Set the game clock at 20 minutes and start the clock. At the appropriate times listed below, players begin their running. They have until the end of the minute to complete one rep. For example: the first rep begins at 19:43 on the clock and they have until 19:00 on the clock to complete the first set.

Here are the times that players begin their run:
20:00 - 19:42 rest
19:43 - 19:00 (17 seconds of rest)
18:43 - 18:00 (17 seconds of rest)
17:43 - 17:00 (19 seconds of rest)
16:41 - 16:00 (19 seconds of rest)
15:41 - 15:00 (19 seconds of rest)
14:41 - 14:00 (21 seconds of rest)
13:39 - 13:00 (21 seconds of rest)
12:39 - 12:00 (21 seconds of rest)
11:39 - 11:00 (23 seconds of rest)
10:37 - 10:00 (23 seconds of rest)
9:37 - 9:00 (23 seconds of rest)
8:37 - 8:00 (25 seconds of rest)
7:35 - 7:00 (25 seconds of rest)
6:35 - 6:00 (25 seconds of rest)
5:35 - 5:00 (27 seconds of rest)
4:33 - 4:00 (27 seconds of rest)
3:33 - 3:00 (27 seconds of rest)
2:33 - 2:00 (29 seconds of rest)
1:31 - 1:00 (29 seconds of rest)
0:31 - 0:00