Summer is here and we’re all trying to maintain our fitness routines. This means hours and hours of cardio, right? Ugh. Not only does that seem overwhelming, time-consuming, and difficult to stick with, but what if there was a way to burn more calories, lose more fat, and improve your cardiovascular fitness level while spending less time in the gym? You’re desperate for a way to get fitter, faster, right? Enter high-intensity interval training, also known as, high-intensity training or HIIT.

For years, I was a middle-of-the-pack long distance runner. I loved a nice, long run; it was always very therapeutic for me and before I became a personal trainer, it was my main mode of exercise. I still enjoy a long run every once in a while, but It wasn’t until I started implementing more high-intensity workouts into my own routine that I really saw a true change in my body: I got leaner and stronger at the same time.

If you’re looking for a way to take your fitness and fat loss to the next level—without spending more time in the gym—then HIIT could be exactly what you’re looking for. To be clear, I am not saying HIIT will be easier, just that it will take less of your time. More appropriately, the HIIT approach to cardio exercise is very physically demanding but, astonishingly, HIIT makes it possible to get more from doing less.

HIIT is a specialized form of interval training that involves short intervals of maximum-intensity exercise separated by longer intervals of low- to moderate-intensity exercise. In a nutshell, it means doing a number of short bursts of intense exercise with short recovery breaks in between.

Because HIIT involves briefly pushing yourself beyond the upper end of your aerobic exercise zone, it offers several advantages that traditional steady-state exercise (where you keep your heart rate within your aerobic zone) can’t provide. HIIT trains and conditions both your anaerobic and aerobic energy systems. HIIT trains your anaerobic system with brief, all-out efforts; like when you have to push to make it up a hill, sprint the last few hundred yards of a distance race, or run full speed into the end zone to avoid being tackled. They push themselves to the capacity then recover and repeat. This shorter, more intense way of working is just that, and also creates a ton of additional benefits.

1. It burn more calories and fat. HIIT increases the amount of calories you burn during your exercise session and afterward because it increases the length of time it takes your body to recover from each exercise session. It also causes metabolic adaptations that enable you to use more fat as fuel under a variety of conditions, which can improve your athletic endurance as well as your fat-burning potential.

2. It preserves muscle. Anyone who has been on a diet knows that it’s hard to not lose muscle mass along with fat. And even worse, steady state cardio seems to encourage muscle loss through the production of cortisol. A study published in the Journal of Obesity showed that both weight training and HIIT workouts allow dieters to preserve their hard-earned muscle, while ensuring most of the weight loss comes from fat stores. Keep the muscle, burn the fat. Perfect!

3. It keeps you feeling young. Not only does HIIT beat conventional cardio as the most effective and efficient form of exercise, it also provides health benefits you simply cannot get from regular aerobic exercise, such as a tremendous boost in human growth hormone (HGH). This is great news since HGH is not only responsible for increased caloric burn, but also slows down the aging process, making you younger both inside and out. It’s almost like a metabolic fountain of youth.

4. It doesn’t require equipment. Running, biking, jump roping, and rowing all work great for HIIT, but you don’t need any equipment to get it done. High knees, fast feet, or anything plyometric like jumping lunges work just as well to get your heart rate up fast. In fact, Fitbit Premium is chock full of awesome workout that will help you feel the HIIT burn. Not a member? Here’s a quick HIIT workout you can do virtually anywhere: Perform 60 seconds of fast, high knees, followed by a 30 second rest. Repeat 6 times.

5. It boosts your metabolism. Several of the genes affected by an acute bout of exercise happen to be the very same genes involved in fat metabolism. Another study in the Journal of Cell Metabolism showed that when you exercise, your body almost immediately experiences genetic activation that increases the production of fat-busting (lipolytic) enzymes. Everyone wants to be a more efficient calorie burner, even at rest, so after you’ve completed a HIIT workout, you’ve not only burned a ton of calories, but also sped up your metabolism. Win-win!

6. It save time. Your life is really packed. It’s always a challenge to squeeze in a workout. Well, “no time to exercise” is no longer an excuse. These quick, efficient sessions leave you with more time to enjoy life while feeling more fit. Remember: You can use Fitbit Coach anywhere, just download the app, and boom, you can try some amazing HIIT moves. It’s right there in your pocket.

7. It’s adaptable. The HIIT approach to cardio exercise is definitely physically demanding, but it can be modified to different levels of fitness. That said, if you have any cardiovascular problems or other health concerns that limit your ability to exercise at very intense levels, or if you are relatively new to aerobic exercise or not already in good shape, HIIT may not be for you—at least for now. If you have any doubts or concerns about whether it might be safe for you, check in with your medical professional before trying HIIT.

HIIT’s just one of many ways you can get fit and healthy. Give HIIT a try today to change up your current workout, or if you’re looking in inject a quick hit of fitness into a jam-packed schedule.