What do you know about spinning? Everyone seems to be talking about it lately and I really don't know what it is, except that it involves a bike and a class. Is it as great as everyone says?

-- Jenny

Jenny, I haven't taken a spinning class, but I have tried the bike used in the class. Think of spinning as an indoor group ride led by a drill instructor. One attraction of the class must be that misery loves company.

You have a group of spinner stationary bikes arranged in a format so that every participant can see the instructor/coach who is also on one of the bikes. The instructor takes the class through a workout/ride of about 45 minutes, barking out commands to sprint, ease up, or add resistance to simulate hills.

The spinning craze was started in California (where else?) by a guy named Johnny G. He designed a stationary bike which looks pretty primitive compared to the electronic, computerized bikes you see in gyms today. It has a huge flywheel which makes it resemble an exercise bike your parents might have owned. But the spinner is deceptive. Getting that big flywheel turning is like starting from a dead stop on a real bicycle.

Once you get it going, the momentum of the flywheel enables you to "spin" the pedals as you would on your bike outside. The ride is closer to that of a real bike than any other stationary bike I've tried. Couple that with a seat that adjusts fore and aft, not just up and down, and multi-position handle bars that also adjust up and down--and you've got a bike that an avid cyclist can get a great workout on while recreating her favorite position on the bike. Some gyms even swap the pedals with toe clips for clipless pedals so that people can wear their own cycling shoes during the class.

When Crunch, a gym here in NYC, started offering spinning classes a few years ago, there was a two week wait to get a spot in a class. Now the classes are more widely available and the Johnny G. Spinner, which is made by the venerable Schwinn bicycle company, has been copied by other manufacturers as well.

WARNING: Once you get that flywheel turning, you can't just stop pedaling. It takes a while for something with that kind of mass to lose momentum and slow down. It's kind of like stopping on a fixed gear track bike. This can take a novice by surprise.

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