6. Planking Frog Tucks
This workout is a very challenging and effective way. It will strengthen the core and flatten your stomach.
How to do it: Start this workout by doing a high position pushup with your body straight from your shoulders and heels. Then, bring your right foot forward, placing it next to your right hand (or as close as you can). Try to keep your hips from rising. Hold for a few seconds and then return to your starting position afterwards. Repeat the same process on the other side.