Why simulate a vertical sweat sesh on a stair climber–esque machine at the gym when you could instead channel your inner Rocky and run up and down a few flights IRL? That’s exactly how Jennifer Lopez and her pro-athlete boyfriend Alex Rodriguez are crushing their New Year’s goals—and you can get quite the workout by following suit.
In Rodriguez’s recent Instagram video, the duo sweat it out at an outdoor track doing some burpees, planks, jump-roping, and even barbell squats. The stairs, though, might have been the hardest part of all: According to one exercise physiologist and trainer, it’s easily one of the most intense forms of cardio around.
“It feels like it’s more work because it is more work,” fitness expert Pete McCall told Self. “On the way up, you’re doing a lot more hip flexion and extension—your hip is going through a much greater range of motion [than with walking or running], so you’re getting more work out of your hip extensor muscles.”
So how do you go about getting a J.Lo-worthy workout? Based on this workout from McCall, simple is best: Just sprint to the top of the stairs for 6 to 10 seconds, walk or jog back down for 30 seconds, and repeat five times. When you’re finished, rest for a couple minutes and repeat the entire process for two or three rounds, depending on how you feel, he said.