If you’re short on time but also serious about losing weight, toning up or losing body fat, you want to get the most bang for your buck during your workouts. What type of exercise burns the most fat in the least amount of time?

While results can vary from person to person, your best bet to burn fat is to have a well-rounded exercise routine that combines cardio and strength training. And to do that in the least amount of time, you will most likely want to try HIIT (high intensity interval training) workouts. You can effectively get a maximum fat-burning workout by rotating between HIIT cardio and strength training all in the same session.

To amplify the intensity of any routine that you do, use a waist trainer to stimulate heat around your core and help you sweat harder.

Burning Fat with Strength Training

A well-rounded exercise routine should incorporate strength training of all muscle groups. You can target large muscle groups in 2–3 sessions per week; just be sure to have rest days in between.

The reason strength training is effective for burning fat is because it stimulates muscle growth around the clock. If you focus on your legs on a Monday, for example, your body will work on rebuilding the muscle you worked for the next day or two, depending on how hard you worked. To build muscle, your body must exert a lot of calories, and some of those calories can come from fat.

Effectively, strength training boosts your resting metabolism since your body will still be working even when you’re not in motion. If you combine strength training with a nutritious diet that doesn’t include excess calories, you will build muscle and lose fat.

Remember, it’s important to maintain a nutritious diet when you’re strength training, especially one with adequate protein (20–30% of your caloric intake) so that your body can build muscle during your times of rest.

Examples of fat-torching strength training exercises you can do with a waist trainer include:

Side crunch leg extension: complete 3 sets of 15 reps.

Oblique hop plank hold: complete 8 sets of 10 reps.

Leg extension crunches: do 6 sets of 12 reps.

Plank twists: do 3 sets of 20 reps.

Bridge pose: do 4 sets of 25 reps.

Leg lifts: do 4 sets of 15 reps.

Total body strength training routine: You can do this workout once or twice a week. Do each exercise 12-15 times per set, and repeat the whole circuit 4-5 times.

Killer booty-building training: Repeat the circuit three or four times to get a full workout in (you can take 1–2 minute breaks in between circuits). You can take 10–15 seconds of recovery time in between each move.

Burning Fat with Cardio

Cardio has many benefits. It burns more calories during your workout session than strength training does alone. The more you weigh, the more you’ll burn. If you’re watching your diet, it can burn fat when you run out of carbs to burn through. For this reason, some people prefer to do cardio after a short period of fasting, such as first thing in the morning.

Not only will it contribute to weight loss (especially if you do it in combination with strength training), but cardio can also help with balance, flexibility, posture and endurance, depending on what kind you are doing. It also benefits your heart and whole cardiovascular system, not to mention your mood and energy level. Even going for walks can cause these benefits, so just because you don’t have time for a long cardio session doesn’t mean you should do nothing.

Remember, you can wear a waist trainer during most cardio exercises to help intensify the workout. Try it with walking, running, cardio machines and biking.

To maximize fat burn, you may want to do cardio on the same day as a strength training session. In this way you’ll burn a lot of your calories during your workout and continue to burn fat when you’re resting. The downside is that this requires more time.

Burning Fat with HIIT

HIIT is a style of cardio workout that cranks up your heart rate in bursts with short breaks in between. Since it requires more energy to act in small bursts, you can essentially burn more calories in a short amount of time when compared with a steady rhythm cardio routine.

HIIT workouts can also be combined with strength training in the same session. Many people prefer doing high intensity intervals in between strength training sets to fit both strength training and cardio into the same workout, with less time.

The one drawback to HIIT (or really any workout that pushes you to your physical limits) is that you can be more vulnerable to injury if you’re not careful. For this reason it’s important to listen to your body, warm up before an intense work, and cool down and stretch afterward. Stop if you feel pain, aside from muscle fatigue, which is normal.

Don’t over-train, as this will work against weight loss because it can put too much strain on your body and land you on the bench. If you’re not sure how much you should be doing, work with a certified trainer.

Some of our favorite HIIT and strength training routines, all of which can be done with a waist trainer, include:

Beginner bodyweight HIIT workout: perform each move for 45 seconds with 15 seconds of rest between moves.

Brutal fat-burning HIIT cardio: combine sprints with the most effective HIIT moves for a calorie-torching workout. Don’t forget you need about 10–15 seconds of recovery time in between each move.

Ab and HIIT workout: Do each exercise in this workout for 30 seconds. Be sure to include about 10–15 seconds of recovery time in between each exercise. Complete the circuit three or four times to complete a full workout, with a 1–2 minute break between each circuit.

With a well-balanced workout routine and a nutritious whole-food diet, you’ll effectively burn body fat and tone up. Good luck!