As the name implies, this is not a pleasant drill to perform but it works wonders for your conditioning. All you need is a kettlebell, sledgehammer and tyre, and a pull-up bar. Also a sick bucket might be useful!! Perform the following as fast as possible for two-three rounds. Rest only 1 min between rounds. Do not rest between exercises!!
100 Sledgehammer strikes into tyre (50 each side)
75 Hindu push-ups
50 Kettlebell squats (rack hold - change hands halfway)
25 Pull-ups/chins
Try to complete the rounds as fast as possible.
As a finisher, try a "race to 50 sprawls".
Perform fifty "1-2-sprawl" combination (throw a quick jab-cross then drop into a sprawl and repeat) as fast as possible. Strive to beat your time each time you perform it.