4 rounds OTC - 

2stab crunches
20 ball kills R+L=1
20 plank tocks R+L=1
20 stab uni hipups R
20 stab uni hipups L

Post Rx or reps completed to comments.

21 Day Extras - for time: 

1000m row (No rower? Do these - 1r = 10m) 
50 burpees
1000m row

Workout Notes - 

This workout ought to be just the thing to help loosen up those sore abs from the extras yesterday. Sound off if you are feeling them! 

Here are some good thoughts for tomorrow. 

Stab Crunches - Be sure to get fully extended back on each rep.  Interlock your fingers behind your head (keep elbows back please).  Flex your trunk as far forward as flexibility will allow.  To scale, simply lower hips below shoulders by walking hips forward.

Ball Kills - Crunch the abs!  Pull back with the arms as your knee makes contact with the ball.  Wider legs puts more tension on the core.  It's good, but its an advanced move.  To scale, hold plank on ball.  Move to knees, if needed. 

Plank Tocks - The ball is going to walk backwards on you.  Follow as best you can.  It will be more tension on your core to resist this.  To scale, walk knees back towards ball; widen the legs; push up to hands.

Uni Hipups - These are not med ball hipups!  It will take much more effort to elevate hips to a parallel line between shoulders and knees.  Vets try hard!  The benefits are worth it.  Keep the other leg locked straight and just hovering above the ball.  To scale, use both legs, or move to floor.