Pick up a jump rope, and you may be transported back in time to high school gym class. The difference? Back then, it was all about fun and games, but now it’s time to stop associating the jump rope with play time. Jump rope workouts are a thing. Fact: more and more CrossFitters are kicking up traditional jumps by slaying double-unders (and even triple-unders) in boxes from Los Angeles to Boston. And boxes and boutique studios alike are using the training tool in fun and creative new ways. Take Equinox, for instance, with their new offering the Cut, a HIIT-focused workout from the team at Equinox, incorporates a weighted two-pound Fury Rope to provide a next-level sweat.

“A jump rope is a must have for anyone serious about their fitness and athleticism,” says Gregory Nieratka, head endurance coach at Solace New York. “Not only is jumping rope a great cardio exercise that aids in weight loss, it also improves your coordination, agility, and foot speed. Those skills will make you a better athlete in whatever you choose to do with your fitness.”

Another great perk? They’re mega-easy to travel with, which means scorching calories is possible no matter where you are. Do jump rope workouts for an hour and you can burn up to twice as many calories as running (depending on your weight, intensity, and speed) and even up your bone density, according to a study published in the Journal of Applied Physiology. Another study of young soccer players revealed the immense balance benefits of jumping rope, too. Researchers found that compared to those who only practiced soccer drills, kids who incorporated jump rope workouts improved their balance and motor coordination more.

Jump Rope Workouts

Ready to get to moving? Try one of Nieratka’s go-to jump rope workouts, which you can crush in under 15 minutes. Note: you’ll see he’s all about the double-unders, which is when the rope passes under your feet two times every time you jump.

“It really amps up your heart rate, thus amps up your workout,” he says. “If you aren’t able to do double-unders yet then scale it back to the traditional single-under. Either way, you will still get a great workout.”

50 double-unders, 50 sit-ups

40 double-unders, 40 sit-ups

30 double-unders, 30 sit-ups

20 double-unders, 20 sit-ups

10 double-unders, 10 sit-ups