If just thinking about a HIIT workout seems tiring, let the music play. A Journal of Sports Sciences study found that when people performed four 30-second all-out sprint intervals on a bike while listening to music, they had a more positive workout experience than when they pedaled without tunes—possibly because music helps distract you from the, uh, discomfort of a tough sprint. Try biking (or running or rowing) it out to one of these songs recommended by Steph Dietz, lead instructor at Cyc Fitness, an indoor-cycling studio chain.
"They’re perfect for intervals because they slowly build to the chorus, where the beat drops, picking up speed and intensity," says Dietz. "Each song has about two or three HIIT interval builds."