Kelsea Ballerini used to be a workout hater. The country star reluctantly agreed to start working out with trainer Erin Oprea, and while she’s still not a huge fan, the results speak for themselves — especially in her abs.
“She might not love working out, but she does it and she does it well,” Oprea tells PEOPLE.
Ballerini, 23, showed off her impressive abs at the CMA Festival in June, and often posts on social media about her desire for a six-pack. She’s working with Oprea, who also trains Carrie Underwood, on getting there.
“Yeah, did you see that ab picture?” Oprea exclaimed. “So much of that comes from eating and drinking, so she has to have the discipline to do that. You can’t do one without the other, you have to do both of them to get the results.”
Oprea, a fitness ambassador for USANA, says that “abs are truly made in the kitchen,” and makes that clear to her clients. And then when they hit the gym, Oprea has a few favorite moves for a serious ab burn.
“This is a favorite of my clients and for me too!” Oprea says. Sit on a Bosu ball, and have your partner stand on your feet. Using a 6-10 lb. ball, move it behind your head and keeping your abs engaged as you lean back. Throw the ball to your partner as you crunch up and repeat as you go back down, catching the ball and keeping your abs tight the whole time.
“No arching of your back!” Oprea adds. “Repeat 10-20 times, but don’t let the move get into your back.”
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“Lay on your back and sit up, while at the same time bringing a straight leg up to meet you. Clap your hands behind your raised leg before returning your leg and upper body down to the ground to repeat clapping behind the other leg. Go back and forth for a total of 10-15 claps behind each leg.”
Side Plank Hip Pulses
“Go into a side plank on your right elbow. Now dip your hips toward the ground (not touching the ground, but close), then bring them back up to neutral. Repeat these dips for 20-45 seconds before repeating the exercise on your left elbow.”
Elbow Plank with Hip Dips
“Go into an elbow plank and dip your hips to each side, while using your abs to engage your body before your hips touch the ground. Bring your hips up and over to each side, repeating for 30-60 seconds.”
Oprea says to do the movements with “as little break as possible” for a serious burn.