Start by lying on your stomach with your elbows propped under your shoulders. Brace your core and raise your body up until only your toes and elbows are on the ground. Don’t look up; pick a spot on the ground so your neck stays packed. Now hold this position until you start to shake and feel like you can’t keep your core braced and spine supported. Holding a plank for excessive time while your shaking like crazy won’t do you any good; you’ll be letting go of your core brace and not properly stabilizing the spine. DON’T HOLD YOUR BREATH! Breathe normally. Once you feel like you can’t sustain a braced core lower yourself to the ground and check your time. If it was less than 20 seconds you should perform 4-5 reps of 20 second planks for 2-3 sets. Once you can hold your plank for 30 seconds perform 3-4 reps of 30 second planks for 2-3 sets. Once you can hold your plank for 1 minute or more do 2-3 sets of 1 minute planks. Once you can achieve a 1 minute plank for 2-3 sets you are ready to advance to Planks with Pulses.