1 - Decline sit ups - x 50, 60 sec rest then another 50.
2 - Seated straight barbell oblique twists 17.5kg bar. x50, 60 sec rest then another 50
3 - Hanging leg raises x 15 no rest then a further 10 holding a 5kg weight with feet. 3 sets 60 sec rest in between.
4 - The plank with 20kg plate on back. Hold for as long as poss.
5 - Kneeling crunches. Hold on the the tricep rope behind your neck and crunche slow and tight. Full rack of weights x 50, 3 sets 60 sec rest
Your abs should be absolutely destroyed by the end of this! Hit Machine Mode and push through the pain.