HIIT stands for high-intensity interval training, a style of training built around repeated intervals of hard work paired with shorter periods of rest or active recovery. This structure makes HIIT a time-efficient way to challenge cardiovascular capacity, build strength, and elevate endurance while helping intensity stay high throughout the workout.

A HIIT workout does not need to be long to be effective. Equinox classes are designed to deliver meaningful results in a shorter time frame by using structured intervals that maximize effort and minimize wasted time. The right duration depends on the format, your experience level, and the intensity of the work, but the goal is always the same: efficient training that drives measurable progress. Equinox offers 30-minute HIIT workouts like Quick HIIT and Core6 Express. As well as full 45-minute HIIT workouts like MetCon3, Stacked, and Hydro Athlete.

Equinox instructors are adept at coaching to all levels, offering modifications, and coaching to the room. Beginners can benefit from the structure, motivation, and clarity that intervals provide, while more advanced participants can push intensity further within the same framework. The key is choosing the right level, moving with control, and building capacity over time. You don’t have to wait until you’re “in shape” to start taking HIIT classes!

You can expect to sweat. HIIT is built around effort — each work interval is designed to push your heart rate up, so you should feel challenged during the high-intensity segments and recovered enough during rest periods to go again. Instructors coach to perceived exertion rather than a single fixed pace, so effort will look and feel different from person to person in the same room. The goal isn't to be maxed out for the entire class — it's to hit genuine peaks of intensity, recover with intention, and repeat that cycle enough times to drive real cardiovascular and strength adaptation.