Lie on your back, and open your legs into a diamond shape (aka butterfly legs) with the soles of your feet pressed together and knees out wide. Extend your
Backup WOD – The Overman Crossfitter
10 Sit-Up Variations (From Easiest to Hardest) - Steel Supplements
Diamond Sit Ups
Bodyweight Resource
Rogue Monster Rhino Belt Squat - Stand Alone
Sit-Ups Benefits: Exercises, Variations, and More
Points of Performance: The Sit-Up - Rhapsody Fitness
CrossFit Bodyweight Workout Resource - NorCal Water Polo
AbMat Sit-Up
How to build core strength when doing core exercise is hard because of back pain - Quora
Abmat - Sit-Ups Are Back
V-Ups, What Are They? Muscles Worked? Benefits?
44 Crossfit Workouts Demonstrated, Your Guide to Crossfit Workouts