Advent challenge - Dec 20
The format of today is the Rolling 20's! You set a timer for 20 seconds (you can use your phone if you like). Every 20 seconds, on the beep, you do the reverse crunch exercise.
Beginners do x6 reps, intermediates do x8 reps while the more advanced will do x10 reps.
20 seconds later, you repeat the process...you don't get any rest time! Keep going for as long as you can keep up with the timer. As soon as you can't complete a round within the 20 seconds, that's it! It's over!