How to Burn 900 Calories in Just One Hour

Piloxing is an amazing full-body workout, and it's also good, dance-y fun, says Kelly Osbourne. She's sweaty but sold.

When I heard that Piloxing could burn a crazy number of calories without bulking up your muscles, I was intrigued. If I do certain intense workouts, I turn around and suddenly my legs look like I'm a quarterback. But in Piloxing class (you can also do it at home with a DVD), you're building muscles and elongating them at the same time. The workout is based on intervals, meaning you're alternating quickly between boxing, standing Pilates, and dance moves. Think Zumba (it's high-energy and set to fun music), only tougher. I really love that Piloxing can be for all body types; everyone from Hilary Duff to Melissa McCarthy has tried it. And it brings out the Rocky in you, as well as your sexy side. Here are a few moves to try:

Related: 21 Ways to Burn Fat Faster

Step 1: Stand on your bent right leg with your left leg lifted and bent. Keep your palms up and by your chest.
Step 2: Straighten your arms and left leg, then return to starting position. Do three sets of eight on each leg.

Oblique box
Step 1: Sit with your knees bent. Hold your fists in front of your chest and lean back, holding your tummy in tight.
Step 2: Twist to the right while punching your left arm across your body, then do the same on the opposite side. Continue for 15 seconds, rest, and repeat two times.

Related: How to Finally Halt Emotional Eating

Piloxing butt
Step 1: Starting on your hands and knees, place your right forearm on the ground under your right shoulder and your left hand on the ground under your left shoulder. Cross your left bent leg behind your right knee.
Step 2: Lift and extend your bent knee toward your shoulder and extend it straight while contracting your stomach. Repeat for 30 seconds, then switch sides.

Kelly's tips:

1. Do it when you feel most awake (or caffeinate beforehand). For me, that's the morning. If I waited to do it after a workday, I don't know if I'd have enough energy for Piloxing.

Related: 25 Lazy Ways to Burn Extra Calories Just Like That

2. Start slow. This isn't the kind of workout you jump into and do five or six days a week. That would leave me in so much pain that I'd think, God, this is awful; I'm never doing it again. So my motto is always: Pace yourself, even if that means you only do it once or twice a week in the beginning.

3. Get more of a calorie burn. I wore the signature half-pound weighted Piloxing gloves during the workout and was amazed by how much harder my arms and abs had to work. You can do it bare-fisted, but the instructor told me you'll burn even more calories after the workout if you do it with the gloves on. And don't worry, you do a lot of arm jabs, but you never actually punch anything.

4. Don't make this a Piloxing party for one. I always find that when I'm doing a really serious workout, it's fun to have someone do it with me. It helps me not give up. Recruit a friend, or you could make your boyfriend or husband join you, because it's got just the right amount of toughness to it.

More from REDBOOK: