If you’re reading this right now, you’re probably in the market for a heart-thumping, blood-pumping, balls-to-the-wall workout. And, friend, we’ve got you covered. We’re all about helping you get sweaty in pursuit of your goals, whether that means getting stronger, hitting a new PR, or losing weight. But let’s be real for a second here: The tricky thing about weight-loss workouts is that they’re kinda, sorta… a myth. Don’t get me wrong—if you’re trying to lose weight, a solid exercise regimen should be part of your plan. It just can’t be the only part.

Here’s the thing: Working out isn’t enough on its own to make weight loss happen. There’s so much else that goes into weight loss and body fat loss; in fact, exercise isn’t even technically necessary in many cases. If you want to lose weight—and it’s totally cool if you do and totally cool if you don’t—adopting healthy eating habits has got to be step numero uno. To get technical, you need to create a calorie deficit, which means using more calories in a day than you consume—and the consumption part plays a much bigger role in that than burning calories in the gym, or while carrying your groceries home, or any of the other myriad ways you put your muscles to work each day. Other lifestyle habits, like sleep and stress management, and health conditions (think thyroid issues, to name just one of many) also affect your weight. Point is, weight loss is a complicated and extremely personal journey that doesn’t look or work the exact same way from one person to the next.

And before we get into it any further, I’d be remiss not to point out another really important detail here: Weight loss isn’t for everyone. For some people, it’s actually much healthier to ignore your weight altogether, or never think about calories, or focus on literally anything else. That’s especially true if you have a history of disordered eating; if that’s you, you should talk to your doctor before going on any weight-loss plan at all. In fact, even if you don’t have a history of disordered eating you should talk to a doctor about losing weight in a healthy way.

Keeping in mind the eating well and the sleeping enough, there are certain exercises and workouts that can be particularly useful in helping you lose weight or burn fat or change your body composition. These workouts tend to have a couple elements in common: They’re generally high-intensity and they burn a lot of calories in a short amount of time. Here are the types of exercise trainers recommend to get the most out of your gym (or park, or living room) time.

1. Interval Training

The number one training method the experts turn to again and again for weight loss: interval training. What’s that? “Any form of exercise where your heart rate spikes and then comes down repeatedly,” says Rilinger. This generally means going hard for a set interval of time (hence the name), followed by active rest, then going hard again. That active recovery portion is key. You need to take it down a notch—OK, several notches—before ramping back up to a higher intensity interval.

High-intensity interval training, or HIIT, is one of the many styles you can do. Another popular one is indoor cycling, though this workout leans heavily toward cardio over strength training, Rilinger explains. She also notes that cycling requires you to use various muscles in your body—quads, hamstrings, glutes, and core, for starters—which once again translates to weight loss. “The more muscles you have to incorporate, the more calories you’re going to burn because those muscles all require energy in order to work,” she says. “And the more energy you use, the higher those calorie-burning numbers climb. It’s all a cycle.”

2. Weight Training

Consider weight training “the mother of all weight-loss techniques, the highest in the workout food chain, the top of the totem pole,” says Rilinger. Resistance training, whether it’s with your bodyweight alone or with added weights, is an effective method to help build muscle and burn fat. Lifting weights has been shown to increase your resting metabolic rate, which means your body burns more calories even when you’re not working out. The effect isn’t enormous, but building muscle means more muscle mass to churn through calories as you go about your day. Plus, more muscle means you can go harder next time, increasing your weight, and getting even more out of each workout. Plus, if you’re lifting at a high intensity, you get the added bonus of the “afterburn effect,” which is when you’ve put down the weights but your body is still using up extra energy.

Rilinger suggests adding weight training to your routine at least three times a week. And since your body adjusts to workouts after being exposed to the same moves at the same intensity, becoming less effective over time, she says to mix it up about every three weeks to keep your body guessing.

3. Boot Camp

For a workout that’s going to keep your metabolism elevated, turn to boot camp, as these classes (think Barry’s Bootcamp) combine two of the most effective styles of training: interval and resistance. “You’ll perform exercises, some more cardio-focused and others strength-focused, full-out for short bursts of time, coupled with short periods of rest,” says Adam Rosante, certified personal trainer and author of The 30-Second Body. But if it’s your first time going to a boot camp class, speak up. He says a good instructor will help you determine when you need to crank up the weight or intensity (tip: if you can cruise through 10 reps without any trouble, it’s too easy), keep your form on par, and can always provide a modification for any move that might be too tough or irritates an injury. If you can’t make it to a studio, though, you can virtually sweat it out with Rosante in his 20-minute C9 Challenge, or try this bodyweight-only 16-minute routine.

4. Boxing

“At its essence, boxing is really another form of interval training,” explains Rosante. But it also makes you feel freaking badass. Here’s the trick to remember: It’s a common mistake for beginners to punch using only their arm strength, but the majority of your power is going to come from your core and you’ll use muscles that are typically ignored in other workouts (hey there, obliques).

It’s best to log this type of workout in a class, as Rosante says it’s crucial for beginners to learn proper form from an instructor who can help keep your intensity level high. Here are 18 boxing gyms worth visiting. But if you want to brush up on your skills at home, try this beginner-friendly video from Milan Costich, founder of Prevail boxing gym in Los Angeles.

5. Running

All you need is a pair of sneakers before you head out the door. But if weight loss is the name of your game, the lackadaisical head-out-for-a-light-jog style of running isn’t the way to go. Instead, find a hill you can sprint up, or crank the incline on that treadmill. “Running up hills forces you to work your glutes and legs—two of your body’s biggest muscle groups—even more, which requires smaller muscle recruitment and more energy expenditure,” explains Rosante. As noted earlier, the more energy you’re using, the brighter that calorie-burning fire burns. But proper form here is key. “Lean into the hill, and drive your knees as high as you can, striking the ball of each foot down directly under your body,” he says. “Keep your hands open and arms bent at 90 degrees, and drive your arms straight forward up to face level, then backward to the top of your back pocket.” And try not to let your arms cross over your body—that’ll just waste the precious energy your muscles need. If you’re training indoors, here are a few fat-burning treadmill routines to get you started.