I recently bought an exercise bike, and I have been really enjoying working out with it. I don't get bored with it as I have in the past with exercise tapes. I want to lose 5-8 pounds and tone up my tummy, tush and thigh areas. Will using an exercise bike do this for me? If so, how often and for how long do I need to use it?

Here's what the using the exercise bike will do: burn calories, increase circulation, improve health and heart, and increase endurance. Same goes for any other good cardiovascular activity such as running, walking, stair climbing, dancing and so on.

Here's what it WON'T do (at least in any significant way): build muscle.

Cardiovascular exercise is one of the best health insurance policies on the planet. But despite its calorie-burning and heart-protecting effects, its effect on weight loss is limited for many people, especially if it's not coupled with dietary change. Cardiovascular activity is great for preventing weight gain and great for weight management, but when used alone, it's not the perfect method for weight loss.

Some people -- and I stress "some" -- may be able to continue to eat as they always have and lose a few pounds just by adding daily or almost daily exercise. Maybe you are one of those lucky few. The people for whom that works tend to have the least weight to lose and are usually eating pretty well to begin with. For most people, however, some kind of dietary overhaul is going to be needed to complete the picture, since any good you do with exercise in terms of weight loss can easily be undone with the wrong diet.

As far as toning muscles, the exercise bike may help a little, especially if you do it at a higher resistance, but I wouldn't expect too much, particularly with the abdominal areas. For toning and shaping you really need to add some kind of resistance training. Resistance training (weights, machines or body-weight exercises like push-ups) has the added advantage of raising your metabolic rate so that you burn more calories at rest, a huge advantage in the weight-loss game.

How often to ride? Since you like it, why not every day? Or five to six days a week? For weight loss, I recommend at least five days a week, though for general health and maintenance you can get away with less. Thirty minutes or more would be my recommendation, though I like mixing it up: do longer rides on some days and shorter rides on others, varying the intensity accordingly.

Some people find they can break through stubborn weight-loss plateaus by breaking up the workout into two parts -- shorter workouts, twice a day. If it doesn't keep you awake, a 15-minute session on the bike before bedtime has been known to help a lot in the fat burning arena. Take a warm bath or shower afterwards, meditate, read or relax, and go to bed afterwards without eating (or at least without eating carbohydrates). Even if you only do this a couple of times a week, you may see significant improvements.

Mix it up, have fun, stay active, experiment, and you'll get where you want to go.

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