Can I get in shape by Rollerblading? Now that spring is here, I can go to the park three or four times a week. How much should I blade, either distance or time-wise, to get in the best possible shape? I'm 25 and not really overweight, but a bit on the flabby side.

-- Ellen

In-line skating is a great way to help get in shape and maintain your fitness, Ellen. You need to get good enough so you can skate smoothly and efficiently for 45 minutes to an hour.

Don't concern yourself with distance yet. If you're a beginner, get a lesson or two so you're comfortable with stopping, turning and going downhill. Once you've mastered the basics, start skating for time. Don't race. The idea is to get used to skating for an hour or so.

Remember: Like biking, blading downhill doesn't expend as much energy as running, so you'll need to spend more time blading than you would running (in order to get the same cardiovascular benefits).

When you can skate easily for an hour, turn your focus to distance. To increase distance, do one of two things. Stay out longer, or skate harder. It's that simple.

To get faster, you need to get lower and more aerodynamic and get more power out of each stride, like a speed skater. All this places quite a strain on your lower back, so you'll have to strengthen it by doing back extensions.

Keep the muscles of your lower back, quads, glutes and hamstrings loose and supple by stretching. Crunches will help strengthen your stomach muscles and take some of the strain off your back.

Of course, you'll also have to strengthen the muscles that do the actual work. Squats, leg presses and lunges will build power in the quadriceps and glutes and help you get more out of each stride. Leg curls will help your hamstrings.

Remember, blading takes energy so you'll need to refuel often. Carry water and energy snacks with you. Get yourself one of those cute fanny packs made specifically for this purpose.

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