Great exercises & variations for abs & core only using Bodyweight (Calisthenics). Routine examples and alternatives/progression exercises.

Hanging leg raises (full) / Strict toes to bar.
(Alternative: Hanging knee raises)
Flutter kicks & Dragon Flag flutter kicks variation
Jack knvies & variations
Hanging diagonal/oblique raises & variation
Hanging oblique/side raises
Plank elbow to knee cross

Be sure to also check out "Strength & Freedom - Bodyweight Training Motivation" - where I am training in Miami (some of the dragon flags from there):
https://www.youtube.com/watch?v=I3X-vZEUeL8
https://www.youtube.com/storyofshirtless

And my Vacation Workout Motivation from earlier this summer:
https://www.youtube.com/watch?v=QBleGBNB99M

The royalty free music used in this video is "Alice" by Lyod is licenced under Creative Commons Attribution 3.0
http://creativecommons.org/licenses/by/3.0/
Music by Lyod (https://soundcloud.com/lyod)
Track: Alice
Track download, terms & license: https://soundcloud.com/lyod/alice

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