Death. By. Sprints.
Wanna build wheels? Prove it.
This is an Every Minute On The Minute workout. Mark off a distance of 10 yards (or mailbox to mailbox). Start with 5 Sprints the first minute (down is 1, back is 2). Rest the remainder of the minute. Then do 6 Sprints the next minute. Rest with whatever time is left. Then 7, 8, 9.... Keep going until you can't finish the required Sprints in that minute. The best I could do is 12 Sprints completed on the round of 19 (14 minutes total). How far can you make it?