Sophia Bush Demonstrated a Clever Way to Make Side Planks Burn Even More

Just last week, Sophia Bush wowed us by conquering some grueling weighted hamstring curls with her trainer Ben Bruno. Now, she's back at it again, but this time, she's shaking things up with some seriously difficult side plank press-outs.

In a video posted to Bruno's Instagram page, Bush is seen holding a side plank on her right side while simultaneously doing 10 reps of weighted chest presses with her left arm. "@sophiabush crushes these side plank press-outs, which is an awesome — but super-challenging — core exercise that you can do with minimal equipment," the trainer wrote in the caption. (Related: Why Side Planks Are Basically the Best Obliques Exercise Ever)

Bruno then shared the benefits of this simple, yet effective exercise. "It's also great for training shoulder stability, too," he continued. "Her form is great, and I'm equally impressed that she went an entire minute without complaining, which is definitely a record," he joked. (Related: Simple At-Home Shoulder Workout with Dumbbells)

At first glance, the move might look easy enough, but if you watch the video, you can see Bush visibly shaking toward the end of her set. To make a point about how tough this workout really is, Bruno also shared a video of NBA player, Bradley Beal doing the same exercise using the same five-pound weight. Beal does progress the move by lifting his top leg, but not without a ton of effort. Just a few seconds into the clip, it seems clear that Beal is straining and using most of his strength to bang out the reps. He even groans when Bruno asks him to pump out a few more than originally planned. "Given that he's one of the best athletes I've ever encountered in the weight room, it gives you an idea of how hard this is," the trainer wrote. (A surefire way to improve your plank strength? Tackling our 30-day plank challenge.)

If you're looking to try this move at home, Bruno advises starting small. "Most of you should do the first one," he wrote, adding that Beal's variation just gives you something to work toward once you master Bush's variation. But regardless of how you attempt this move, form is key, Bruno shared. "In both variations, you want to make sure to maintain a straight line from the bottom foot all the way through the head and keep the body as still as possible while you press," he explained. "If you're stuck training at home (or even if you're not), give these a shot."

Looking for more ways to level up your core workouts? Check out these 16 ab exercises guaranteed to make you feel the burn.