We’ve all been there: That moment in a workout when you don’t think you can keep going. Then, a song changes, or a beat drops, and you find yourself pushing harder and faster toward that endorphin high.

“The right playlist can help you go further, move longer, give you confidence, and make working out so much more fun!” says Apple Fitness+ trainer Kim Ngo. “That’s why all of our playlists on Fitness+ are curated to give you the energy and motivation you need at exactly the right time. We love building in a big beat drop at the moment when we know users will need it the most.”

Although Fitness+ subscriptions used to only be available to Apple Watch users, Apple recently announced that all iPhone users would be able to subscribe starting this fall. One major differentiator from other digital workout programs? Fitness+ class playlists, which trainers craft for every class. With the help of curators at Apple Music, the teachers themselves pick the songs and order them so that they correspond with each and every exercise to create a motivational workout playlist. While scrolling classes, you’re able to see the genre of music each workout features. And when you click into a class, you can also see a list of all the song choices at the bottom. Some classes, under the Artist Spotlight series, even let you rock out to an entire playlist of one particular musician or group, like BTS, Elton John, or Daft Punk

So what does it take to find the right music to push you through the toughest parts of your workout? We asked the expert Apple Fitness+ music curators and trainers about how they make such motivational workout playlists—especially for those moments when they know you’ll need that extra boost.

Select songs that you take you back to good times

Jesse Blake, global fitness editor for Apple Music, says his approach is “making sure the trainer is intimately connected to each of the song choices. Ideally, it should feel like a personalized mixtape they’ve designed for each workout.” We all know the power of suddenly hearing a song from our past that we have a special bond with.

Use different beats and styles to drive each movement

That said, experimentation—especially with different musical elements— is also key.

“When curating the music playlist for a workout whether treadmill or HIIT, I like to experiment with different tempos to drive motivation and help users reach their full potential,” says Fitness+ trainer Jamie-Ray Hartshorne. “It’s natural to add speed or intensity during high tempo songs but even slower tempo music with a hard beat and a lot of emotion can be just as motivating, and exactly what you need to help you push through when you’d rather back off.”

Other elements the trainers play around with include genre and BPM (beats per minute). A higher BPM song will be faster, so it might motivate you to pick up the pace. A lower BPM song might be just the slow and steady beat you need to make it through a session of heavy lifting.

The Fitness+ trainers also experiment with different genres for different workouts. “If we are pushing through hard and challenging intervals together in a cycling workout, I’ll throw in songs with a heavy hip hop or pure dance beat,” Fitness+ trainer Ty Désean says. “In other rides, I may even look for a more emotional message through the lyrics. If I’m really in the mood to show all sides of Ty, I will add a few musical theater dance tracks to help liven up the party and help you stay motivated and inspired.”

Consider the mood you want to create

Setting the tone of the workout is another major consideration. “Music is such an awesome tool to set and carry the energy of a workout as well as add all the feels,” Fitness+ trainer Jessica Skye says. “For example, a playlist for a slow flow yoga practice is all about creating a mellow mood to help users feel calm, relaxed, and centered. So I’ll lean into everything from the tempo, key, type of percussion, and sounds to try to create an audio experience that matches the flow.”

Ready to create your own playlist? Think of it as an opportunity to connect with music you love, experiment with new genres, tap into your emotional needs, and add variety and drama around the corner. Then add in your own personality to liven up that party. You’ve got this!