Plank: Assume a push-up position with your forearms on the ground and your body in a straight line from head to heels. Engage your core and hold this position for as long as you can.
Bicycle Crunches: Lie on your back, bring one knee towards your chest while simultaneously twisting your torso to touch your opposite elbow to the knee.
Russian Twists: Sit on the floor, lean back slightly, and lift your feet off the ground. Hold your hands together or use a weight if desired, and twist your torso from side to side.
Mountain Climbers: Start in a plank position, then bring one knee towards your chest and quickly switch legs in a running motion. Keep your core engaged throughout the exercise.
Flutter Kicks: Lie on your back with your hands under your hips for support. Lift your legs off the ground and perform small, quick fluttering movements with your feet.
Leg Raises: Lie on your back with your hands under your lower back for support. Lift your legs towards the ceiling and slowly lower them back down without touching the ground.
V-Ups: Lie on your back with your arms extended overhead. Lift your legs and upper body simultaneously, reaching your hands towards your toes to form a "V" shape with your body.