Lie on your back with knees bent and feet flat on the floor. Lift your upper body towards your knees, engaging your core muscles.
Sit on the floor with your knees bent and feet lifted. Twist your torso from side to side, touching the floor beside you with your hands.
Get into a push-up position, but with your weight on your forearms. Keep your body in a straight line from head to heels, engaging your core.
Start in a plank position, then alternate bringing your knees towards your chest in a running motion.
Lie on your back with your hands behind your head. Bring one knee towards your chest while simultaneously twisting your torso to bring the opposite elbow towards the knee. Alternate sides in a cycling motion.
Lie on your back with your legs straight. Lift your legs towards the ceiling, keeping them straight, then lower them back down without touching the floor.
Lie on your side with your elbow directly beneath your shoulder and legs stacked on top of each other. Lift your hips so your body forms a straight line from head to heels, engaging your core.
Lie on your back with your legs straight. Lift your legs a few inches off the ground and alternate kicking them up and down in a fluttering motion.
Stand with your feet shoulder-width apart and hands on your hips. Slowly lean to one side, keeping your torso straight, then return to the starting position and repeat on the other side.
Stand with your feet hip-width apart and hands behind your head. Lift one knee towards your elbow on the same side while crunching your torso sideways, then return to the starting position and repeat on the other side.