The most important type of core exercises you should do are anti-extension exercises. In other words, you must be able to resist arching at the lower back. This is CRITICAL.
The Hollow Body Hold is by far one of the best calisthenic ab exercises you can do. This exercise builds strength, and stability, and helps develop total body control.
Your goal shouldn’t be to hold a plank for 5 minutes. Rather, you should use this powerful exercise to learn how to maintain a neutral spine under varying levels of difficulty.
The next exercise is the L sit. This exercise is essential for improving the strength of your lower abs as well as your hip flexor strength.
This reverse crunch is performed by lying in a supine position (on your back) and lifting and drawing your legs towards your chest.