Crunches and sit ups are great for abdominal/core strength. This is a 30-day challenge that increases the number of crunches or sit ups you do each day for 30 days.

Challenge:
Day 1: 40 crunches or sit ups
Day 2: 45
Day 3: 50
Day 4: rest
Day 5: 60
Day 6: 65
Day 7: 70
Day 8: rest
Day 9: 80
Day 10: 85
Day 11: 90
Day 12: rest
Day 13: 110
Day 14: 115
Day 15: 120
Day 16: rest
Day 17: 130
Day 18: 135
Day 19: 140
Day 20: rest
Day 21: 150
Day 22: 155
Day 23: 160
Day 24: rest
Day 25: 180
Day 26: 185
Day 27: 190
Day 28: rest
Day 29: 195
Day 30: 200

How-to: https://www.youtube.com/watch?v=1fbU_MkV7NE

Rules

Personal challenge that lasts for 30 dage

You update the results of this challenge manually here on the challenge page

You start this challenge when you want