Every 3 minutes for as long as possible complete:
From 0:00-3:00
2 rounds of:
10 overhead squats (43 / 29kg.)
10 chest-to-bar pull-ups

From 3:00-6:00
2 rounds of:
12 overhead squats ( 43 / 29kg.)
12 chest-to-bar pull-ups

From 6:00-9:00
2 rounds of:
14 overhead squats (43 / 29kg.)
14 chest-to-bar pull-ups

Etc., following same pattern until you fail to complete both rounds