Is it necessary to use weights with resistance exercises? Can I just do push-ups and squats at home without weights?

Yes, your very own body can function as strength equipment. You can lift it, lower it, curl it, twist it and bend it in all sorts of ways that are designed to increase your strength. I'm talking leg lifts, push-ups, squats, pull-ups. When you move your body weight, you're fighting gravity -- and that can be a considerable fight.

The advantages to using your body as a weight machine: You don't require any more storage space than, say, your bed. You certainly can take yourself with you anywhere. And the coolness factor is high: Push-ups and pull-ups are impressive, and they call upon just about every muscle in your body. If you're really serious about building upper-body strength, push-ups and pull-ups are useful additions to your strength-training arsenal.

The drawbacks: Ever try a pull-up? They're darned hard. Most people can't do any until they've spent at least a few months lifting weights. And then, eventually, you'll have the opposite problem: The exercises will be too easy. You'll need to add some additional weight rather than increase the number of repetitions you do to infinity. With some exercises, like leg lifts, you can always add an ankle weight or a band. But with other exercises (squats, for instance), this presents more of a challenge. Plus, you need at least some equipment, even to start. Pull-ups require a bar. Some exercises require a chair or two. It's tough to get by without ANY equipment at all if you're aiming to do a full body workout.

If using your body weight alone isn't cutting it but you don't want to spring for a big-bucks weight setup, consider using exercise tubing or exercise bands. Exercise tubing can be purchased in fitness catalogs and is basically the same as the tubing you find in a medical-supply store -- it just comes in brighter colors. Sometimes the tubing has handles or buckles attached to each end, or it comes in a kit with attachable plastic bars and door attachments. The other option -- the exercise band -- is just a long, flat, strong sheet of rubber.

You can exercise virtually every muscle group in your body with bands and tubes, although they work better for certain exercises than others. They take up zero space, and they're portable. They're easy to adjust, too; to make an exercise tougher, use a shorter or thicker band. They're also cheap: You can purchase a couple of bands for under $10. Even if you go hog-wild, you'd have trouble spending more than 60 bucks on a set of bands, a travel bag and a video.

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