This exercise works your core, as well as your chest, shoulders, lats, triceps and quads, explains Michaels. Since burpees involve explosive plyometric movement, they'll get your heart pumping too.

How to do burpees: Stand with your feet shoulder-distance apart and send your hips back as you lower your body toward the ground in a low squat. Then, place your hands right outside of your feet and hop your feet back, allowing your chest to touch the floor. Push your hands against the floor to lift your body up into a plank and then jump your feet just outside of your hands. With your weight in your heels, jump explosively into the air with your arms overhead.

Like burpees, Michaels is a fan of this moving plank exercise because it works your core, in addition to a slew of other body muscles.

How to do mountain climbers: Get into a high-plank position with your wrists directly under your shoulders. Keep your core tight, drawing your belly button in toward your spine. Drive your right knee toward your chest and then bring it back to plank. Then, drive your left knee toward your chest and bring it back. Continue to alternate sides.

The Russian twist is a core exercise that improves oblique strength and definition, explains DiVecchio. The move, typically performed with a medicine ball or plate, involves rotating your torso from side to side while holding a sit-up position with your feet off the ground.

How to do Russian twists: Sit up tall on the floor with your knees bent and feet off the ground. Hold a medicine ball with your hands at chest height. Lean backward with a long, tall spine, holding your torso at a 45-degree angle and keeping your arms a few inches away from your chest. From here, turn your torso to the right, pause and squeeze your right oblique muscles, then turn your torso to the left and pause to squeeze your left oblique muscles. The movement should come from your ribs and not your arms.

Running at an incline rather than on a flat surface has been shown to increase total calorie burn by as much as 50 percent, says Jill Penfold, a Los Angeles-based personal trainer. Whether you're outside on a hill or at the gym on an inclined treadmill, start out walking for five to 10 minutes, suggests Penfold. "Your heart rate should elevate pretty quickly as you pick up your pace," she says.

Try this treadmill workout: Walk or jog on an incline for five to 10 minutes. Maintain a jog for another five to 10 minutes, then pick your pace up again and start running. "This doesn't have to be an all-out sprint," says Penfold, but you should be working hard enough that you can't carry a conversation. Spend five minutes running, then drop your pace back down to a jog. Continue alternating with five to 10 minutes of jogging and five to 10 minutes of running for 30 to 45 minutes.

While the old thinking was that steady-state cardio sessions were best for burning fat, we now know that short and intense bursts of fast-paced cardio is much more effective.

Related: HIIT Training For Fat Burn

Try this HIIT workout: After a 10-minute warm-up, spend 30 seconds doing as many reps as possible of squats, push-ups, kettlebell swings, or single-arm rows. Then, rest for 30 seconds and do a different exercise for another 30 seconds. Continue for 10 rounds. Choose any of your favorite exercises—just make sure you alternate between exercises that work different muscle groups, which will help certain muscles recover while you work others.

"It seems so simple, but 45 to 60 minutes of brisk walking every day can do wonders for your metabolism,". "Plus, it ensures that you don't over-train, which can lead to an over-production of cortisol—a stress hormone that's been shown to contribute to belly fat."

If your walking workout helps you unwind after a stressful day or work through emotions that might otherwise stress you out, there's a chance it'll help you lower cortisol levels, which in turn can keep belly fat in check. And brisk walking is an effective way to drop pounds—including the belly fat that's hiding your abdominal muscles. "One hour of rapid walking a day can lead to one pound of fat loss a week,".