Slow and steady wins the race? Well, not always. Although it seems logical to assume that the farther and longer you run, the more in shape you’ll be, it turns out that bursts of short, intense activity may be the key to shredding fat and dropping pounds.
Unless you’ve been hiding under a rock, you’ve probably heard of high-intensity interval training, or HIIT—after all, it’s all the rage in the fitness world today, and for good reason. HIIT refers to a training technique that involves alternating rapid, intense periods of exercise with brief, moderate-intensity recovery periods. Because you never allow your heart rate to completely calm down between intervals, HIIT scorches a maximum amount of calories in minimum time. Here’s an example of a HIIT workout: sprint one minute, jog for two minutes, repeat. Other examples of HIIT include plyometric training (i.e., box jumps) or Tabata workouts (20 seconds of work followed by 10 seconds of rest).
High-intensity interval training has several advantages over steady-state cardio—it’s been proven to improve endurance, build muscle and increase fat burn more effectively than old-fashioned aerobic training. Read on for five scientifically-proven reasons to hit up HIIT training.
Greater calorie burn. HIIT workouts burn more calories than traditional workouts, especially after the workout. The two-hour period following a workout is referred to as EPOC (excess postexercise oxygen consumption), and it’s when the body works to restore itself to pre-workout levels, in turn using more energy. According to the American College of Sports Medicine, because of the vigorous nature of HIIT workouts, the EPOC generally tends to be greater than normal workouts, burning an extra 6-15% calories overall. This means you’ll continue to fry calories after the workout is over, even if you’re chilling on the couch. Pretty cool, huh?
Greater efficiency. Let’s face it: Jogging 6 miles before work is time-consuming (not to mention, monotonous). Super-efficient HIIT training, on the other hand, is more conducive to a jam-packed lifestyle—you can knock out a killer workout in 20 minutes or less. And you’ll get fitter in a shorter amount of time. According to a 2011 study presented at the American College of Sports Medicine Annual Meeting, just 2 weeks of high-intensity intervals improves your aerobic capacity as much as 6 to 8 weeks of endurance training. So ditch the slow, drawn-out treadmill runs and crank up the speed for an uber-effective workout!
Better heart health. It’s already a well-established fact that cardio is great for maintaining optimal heart health, but researchers are starting to believe that HIIT-style workouts might be an even more powerful boon to your ticker. In arecent 2014 study out of the University of Copenhagen, vigorous HIIT-style workouts helped heart transplant patients keep their blood pressure levels in check better than moderate intensity exercise. This research suggests that high-intensity exercise might be a safe and efficient way to manage blood pressure in the long-term.
Greater endurance.It seems logical to assume that the longer you workout, the more in shape you’ll be, but that’s not always the case. HIIT helps you reach your full athletic potential in less time by challenging both aerobic and anaerobic systems. During high-intensity surges, you’re supposed to go all-out—until you reach that breathless, “OMG-I-can’t-take-this-anymore” feeling. When you feel as though your heart is about to pound out of your chest, it’s a sign you’ve crossed over into the anaerobic zone. Pushing yourself like this can help you become stronger and fitter over time. For example, a 2005 study found that sprint interval training almost doubled endurance capacity in cyclists over a two-week period. By contrast, cyclists who cycled for longer periods at the same pace saw no marked fitness gains.
Fat burn.Not only does it blast calories like crazy, HIIT training also sends your body into fat-burning overdrive. According to a 2008 study, high-intensity interval training increased the ability of muscle to oxidize fat and carbohydrates in sedentary individuals. A separate study from Ontario’s University of Guelph showed that a total of seven hours of HIIT over two weeks raised women’s fat-burning power, compared with 12 hours of medium-speed sessions. Bottom line, HIIT burns more fat in less time.
So should you abandon your long runs altogether? Of course not! Regular cardio comes with many of the same benefits as HIIT, from fat burn to greater endurance to reduced heart disease risk. But for time-crunched folks, or for those who feel like their progress has stalled out, it might be beneficial to switch things up with sprint intervals a few days a week. Not only will HIIT training help you beat workout boredom, you’ll also get stronger, fitter, and slimmer.