The classic abdominal strength training exercise guide.
Fitstream: Bodyweight exercises
Sit-up exercise instructions and video
Fitstream: Bodyweight exercises
Fitstream: Bodyweight exercises
How to Planche (with Pictures) - wikiHow
Bodyweight Workout For Women
Fitstream: Bodyweight exercises
Bodyweight Workout, 20 Minutes
How to do a Sit Up
Sit and Get Fit Day 1