As a former U.S. Marine, Erin Oprea is dedicated to fitness. Now a Nashville-based personal trainer with clients like Carrie Underwood, she uses her expertise to help those with busy lives stay fit. Visit her site or follow her on Twitter @erinoprea. Then come back to PEOPLE.com every Thursday to master a new workout move.

Strengthening your core is paramount to creating a healthy, strong body. It’s also essential for when temperatures reach those that don’t include baggy jackets and bulky sweaters.

Now is the time to really get a hold on your healthy eating, hydration and workouts to really get yourself ready to shine in that summer bikini.

Now, we know only doing one move won’t get you there completely, but adding in my chops exercise, will definitely set you on your way. The combination of engaging your legs along with twisting your core, will give you a good burn the next time you sweat it out!

Grab a 6-15 lb. medicine ball, bowling ball or kettle ball — whatever you have around the house — and get ready to chop away.

Chops

1. Start down in a sumo squat, toes pointing at 45 degrees.

2. Lock your arms out in front of you as you hold the ball near your left knee.

3. Keeping your hips squared straight ahead, stand and bring your medicine ball up and to the right. DON’T bend your elbows, DON’T stand all the way up and DON’T twist your hips!

Photo: Courtesy PEOPLE Great Ideas/Zach Harrison Photography

4. Return down to the starting position to repeat the maneuver 10-15 times before switching sides.

5. Shoot for 3-4 sets as you mix this in your next workout.

Remember: Summer bodies are made in the winter. So, jump on the bandwagon now — and make sure you’re having fun!

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