High Intensity Interval Training (HIIT) is any type of workout where you work as hard as you can for short, intense intervals with brief recovery in between. Designed correctly, HIIT workouts will be a combination of cardio + strength intervals and get your heart rate pumping–but for shorter time periods than traditional workouts (usually between 15-45 minutes.)
Why are HIIT workouts so effective? Dr. Jenni Bruning Brown, owner of Fly | A Fitness Revolution and sport psychologist, says that research has long shown the benefits of HIIT, and it has been used by professional athletes and their trainers for a long time due to its overall effectiveness.
“Studies have shown that longer, steady state workouts at a more moderate or lower intensity are not nearly as effective as shorter, high intensity workouts,” Jenni says. Jenni explains that HIIT workouts have been shown to be better for building muscle, improving endurance and burning fat for long periods (think a slow, easy jog compared with short burst sprints.)
Not only will you build lean muscle, but after HIIT workouts, your body still continues to burn fat and calories, an effect called “the afterburn.” Jenni says that this happens because during a HIIT workout, you are working your system harder than a more moderate workout. Afterward, EPOC (excess post oxygen consumption) occurs, which is your body’s way of using its own energy to restore and recover, and which subsequently also causes you to burn more post-workout calories and fat.
“You don’t have to do much else,” she says, because if you combine HIIT workouts in a variety of areas (think cycling sprints and weight-based HIIT classes), “you’ll get the most effectiveness and efficiency from your workouts.”
Still thinking you need those 2 hour gym sessions? Not so, says Jenni. “Forty five minutes of a HIIT session will do it all. It will build your lean muscle and get your metabolism revved for up to 24 hours.” This body activation is more than any other workout, and includes strength and cardio benefits. Not only that, she says that pushing yourself harder than your typical workouts is something that makes many people feel mentally stronger, too. “Pushing yourself past boundaries is a great way to test your limits,” she says, “and to see what new levels you can achieve.”
Thinking of trying a HIIT workout? Try any of Fly’s 3 weight based HIIT classes, and book on MindBody to level up:
Fly high: weight circuits + cardio intervals (with treadmills)
Fly fire : weight circuits + cardio intervals (no treadmills)
Fly circuit : cardio and weight circuits (low impact, high intensity)