
"If you do the same workout all the time, you won't make progress," says Dan Roberts, celebrity trainer and creator of Methodology X. "The key to losing weight is to exercise intelligently and to truly challenge your body every time you hit the gym."
If you really want to start seeing those pounds melt away, try these high-intensity workouts on for size, compliments of Jim White, ACSM Health Fitness Instructor, Registered Dietitian and owner of Jim White Fitness & Nutrition Studios. They're insanely tough—but not insane (or "Insanity").
Tabata
Based off the same principles as HIIT, Tabata uses high-intensity movements, but follows a specific timeline, whereas HIIT workouts can vary greatly as far as length and the amount of time you spend performing your high-intensity movements. Tabata uses cardio- and strength-based exercises like high knees, pushups, mountain climbers and burpees to get your heart rate up. "Tabata is set out to be 20 seconds of exercise followed by 10 seconds rest, repeated 8 times. Typically at the end of the first round (after all 8 repetitions), a longer period of rest is given, and then another round is started for a total of 20 minutes," White explains. "Tabata can be performed one to three times per week depending on your current fitness levels. I wouldn't recommend it as the only type of workout you do, or the workout you do every day, but throwing it in at least once a week is a great way to torch calories and confuse the body from whatever routine it's used to," he adds.
What You'll Get: A total-body workout for less time than it takes to watch one episode of your favorite sitcom — that won't short you on the calorie burn. Those who work out with tabata burn an average of 15 calories per minute over the course of the 20 minute workout, according to research.
HIIT

Short for "high-intensity interval training", HIIT involves short bursts of high-intensity exercise like sprints or squat jumps followed by a longer, low-intensity phase that White refers to as "active recovery." And, because the high-intensity phase is measured by effort instead of weight or duration, it's one exercise worth keeping in your schedule. As your fitness level improves, so will what you define as 80% — the amount of effort called for in this short bursts of intensity. It's a workout that evolves with you. Since HIIT requires a lot of energy and, therefore, longer periods of rest, White suggests incorporating a HIIT cardio session into your workout routine one to two times per week.
What You'll Get: "The main point of HIIT is the excess post-oxygen consumption 'EPOC'. In other words, 24 hours after your workout, your metabolism is still revved up," says White. Even better: HIIT burns a lot of calories in a short amount of time, making it perfect for those days when you're pressed for time.
Stair Stepper
Forget the treadmill and elliptical; the stair stepper can help you break out of your workout plateau and send your body into fat burning mode almost instantly. "It engages the legs and glutes in a different fashion than running. Rarely do you see people climbing stairs as their typical workout, which is why it will torch even more calories. Proper form is a necessity to avoid injury, though. Maintain good posture and forgo holding on to the handlebars to really ramp up the intensity," says White.
What You'll Get: Muscle confusion and therefore a higher calorie burn. Treadmills and ellipticals tend to be the most popular pieces of equipment in the gym because we are used to them and the movements they require. It's easy for your body to get used to the treadmill and elliptical; since the stair stepper forces your muscles to work in a different way, your body has to work harder and, as a result, burn more calories. According to White, a 150-pound person can burn 131 calories in just 15 minutes on the stepper.
Intense Cycling
SoulCycle, Crank and Flywheel aren't just trendy places to workout, the high-intensity cardio sessions will burn fat and have you dripping in sweat. While prices may be a bit steep, it pays to get in on a class because it's much more difficult to get the same results by hopping on the stationary bike solo. "When engaged in a class you are less prone to quitting," White explains, adding, "Instructor tend to motivate people to work at higher intensities, leading to an increase in calories burned."
What You'll Get: A serious workout session that will have you seriously sweating — and burning calories to match. "A 150-pound person can burn up to 700 calories in a one-hour spinning class working at a moderate-high intensity," says White.
Rowing
You may be seated, but your body is in full motion with this workout. "Talk about a total body workout! Rowing works both the upper body and lower body, and is an incredible cardiovascular workout," says White. If you're a little uncomfortable approaching the rowing machine, most gyms and studios are now incorporating this machine into workout classes. Get in on one to get familiar with this machine with the help of a pro. Chances are it's the least-used at your gym, but it will require your body to use more energy and different muscles than the treadmill or elliptical.
What You'll Get: A full-body workout that will get your heart rate up and your body moving in a new and interesting way. "A 125-pound person can burn 510 calories per hour of vigorous stationary rowing," says White.
TRX
TRX stands for "Total-Body Resistance Exercise," and you better believe it will work your entire body. The set-up is very minimal, comprised of two straps that hang from an elevated place with loops for hands or feet. It uses your own bodyweight as resistance instead of traditional weights or machines. Don't be scared off by the unique setup; people of all fitness levels can use it. While it's possible to purchase a kit for your home, it's best to try TRX with a trainer or in a class setting to reap the most benefits when you're starting out.
What You'll Get: "Research supports that adding resistance training into your regular exercise program will aid in weight loss because it supports muscle growth, and muscle burns more calories than fat and as a result will help reduce overall body fat," says White. A one-hour TRX class can burn anywhere between 360 and 530 calories.
Tennis
Break out your racket! Whipping that ball around will actually whip you into pretty good shape. When it comes to staying on track with your workouts, White says it's all about variety, and a game of tennis with a friend can help you break out of workout monotony. "Play singles rather than doubles to ramp up the fat burn even more," he adds.
What You'll Get: "A 160-pound person can burn 580 calories in a one-hour game of tennis — that's much more than a one-hour elliptical session, which will burn around 365 calories," says White. What's more, tennis involves a lot of short, intense sprints on the court, which not only kick up the fat burn, but also improve your agility and coordination.
Boxing
The workouts that are going to burn the most fat are the ones that do two simple things: make you work your entire body and combine both cardio and strength training. "Boxing is the cream of the crop, when it comes to a total body workout and burning calories. It requires strength, power and endurance. When you throw a hook, it takes serious power and strength. To sustain a punching combination — for example, jab, hook, uppercut — requires stamina for a period of time, resulting in a great cardio endurance workout. What it comes down to is, in order to maintain all of that activity, you have to be burning a lot of calories," says White. Don't be intimidated by boxing — classes can accommodate all levels. You don't have to be Rocky to get a rock-hard body with this workout; your best one-two combination at any level of fitness will fire up your fat burn.
What You'll Get: "The mixture of high-intensity impacts and quick speed fires up the metabolism and increases the heart rate dramatically," says White. If you can boost your metabolism like this, your body will burn calories more efficiently and result in more rapid weight loss if you're consistent with the workouts.
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