1: "Planks are a great core exercise that targets multiple muscles at once."

2: "Crunches are effective for targeting the upper abdominals and can be done anywhere."

3: "Russian twists work the obliques and improve rotational strength in the core."

4: "Leg raises target the lower abs and can be modified for different fitness levels."

5: "Mountain climbers are a dynamic exercise that engage the entire core."

6: "Flutter kicks are a challenging exercise that target the lower abs and hip flexors."

7: "Bicycle crunches engage the obliques and help improve core stability."

8: "Plank variations like side plank and forearm plank offer a full core workout."

9: "Dead bug exercise strengthens the core and improves stability in the lower back."