Keeping Fit With Kickboxing

The Tae Bo craze has given a boost to one of the hottest fitness trends this year, martial arts-based aerobic classes, commonly referred to as cardio kickboxing.

But, as CBS News Saturday Morning's fitness expert Bonnie Kaye reports after attending this year's IDEA World Fitness Conference, not everyone is doing it safely.

You've probably seen the Tae Bo infomercial: all those celebrities punching and kicking their way to a better body with kickboxer Billy Blanks. Anything having to do with punching, kicking, in particular, kickboxing is in this year.

This high energy, sweat-dripping, heart-pumping workout can burn up to 500 calories an hour, toning the entire body while providing great cardiovascular benefits. But its overwhelming popularity has pros and cons.

"If this phenomenon has attracted more people into the gym, great," says Keli Roberts, kickboxing instructor.

"More people are going to be active. Unfortunately they aren't at the right condition to start," she warns.

But, she says, many enthusiastic exercisers jump into the program without having a base level of fitness first, and their muscles simply aren't ready for the high intensity workout. The American Council on Exercise (or ACE) calls the twisting and kicking motions in these workouts high risk moves that can lead to injuries.

"Ankle injuries, knee injuries, hip injuries, muscle strains, muscle pulls," as ACE chief exercise physiologist Richard Cotton rattles off. "There's also a higher risk for some back injuries, especially if you're not in shape and aren't progressing into it gradually."

Even if you are in shape, there's the issue of technique, as martial arts-based moves take time and practice to master them effectively.

"I tell people go and take some martial arts classes, see what it's all about from the real initiation, from its origins. Then you'll really understand the movements," Roberts says.

Roberts gave the following pointers for safe kickboxing:

Don't hyperextend your elbows during punches.
On your jab, come out to about 95 percent full extension so you don't lock the elbow.
Make sure your shoulders are above the hips and your foot and torso turn while performing cross-punches.
See that the hip is rotating.
When kicking, don't lock out or hyperextend your knees. Beginners should modify their kick into a knee lift or kick very low to start.
You need good flexibility for kicking; most people don't have it, so keep your kicks low.
Proper foot placement during sidekicks and roundhouse kicks is key. Your heel faces the hip. The hip is rotated. Hold the base foot so it rotates toward the direction of the kick.

Prepare your body for the rigors of kickboxing with training drills that mimic the movements and that strengthen the muscles used in the class. Roberts teaches a circuit-training class designed for kickboxers with punching, kcking, jump roping, ball throwing and agility drills.

Prepare your muscles properly and go at a gradual, progressive pace for your fitness level to achieve the the gains and strains associated with this popular fitness activity.

Take an introduction class from a qualified instructor who shows how to properly warm up and who breaks down the fundamentals first. It's a great workout but it may not be for everybody or may need modification to prevent injury.

For more on kickboxing and exercise, visit the ACE Web site.

And for more infomation on the 1999 World Fitness IDEA Convention, go to www.ideafit.com. The conference gathers fitness professionals to exchange ideas and share the latest workout trends.

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