Using the tall plank described in Day 2, we are going to increase the difficulty rating by taking turns raising hands off the floor. If you have never done this before, begin with hands close to each other with feet at least shoulder width apart. Begin with proper form and brace everything for the work ahead. Raise left hand about an inch off the ground, hold it there for 3-5 seconds. Lower it back to the ground with control. Do not land heavily on the hand. If it just isn't possible to raise one hand while keeping a perfectly flat back (with no torso tilting) , then challenge yourself to foot lifts instead.
As with yesterday's challenge, today's is all about changing from side to side often, to test yourself and not allow any tilting as you switch hands. Try to hold palm off the floor for 3-5 sec before returning it. If this is too easy, you can advance it by following the example up above... take your time and extend your whole arm out in line with your spine, stretch hand far away from hips and return slowly to repeat on other side. Today's goal is to perform this exercise for at least the same duration as you did in a Day 2. Take breaks as you wish, but do challenge yourself. It's all about quality, holding form every switch and switching from hand to hand often. ( at least 11 switches per min!)