spiderman plank
Start in a traditional plank position with your forearms on the ground and your body perfectly straight.
Bring your right knee forward towards your right elbow, then return to the plank position.
Repeat by bringing your left knee toward your left elbow.
Alternate sides for a total of 10 or 20 depending on your level.
side plank
Lie on your right side, in a straight line from head to feet, resting on your forearm. Your elbow should be directly under your shoulder. lift your hips off the floor, maintaining the line. Keep your hips square and your neck in line with your spine. Hold 20 to 40 seconds and lower
full sit ups
Start on your back with your legs stretched out and your hands laid out above your head.Without using momentum, fully sit-up and reach for your toes.Roll back down into the starting position with full control.