I just started back jogging after a one-year "lazy" leave of absence. Day one was terrible -- I could only run one mile without my heart throbbing and my lungs burning. To add insult to injury, it took me 12 minutes to do it. What can I do to increase my endurance and speed without having a heart attack?

--liz

First, congratulations for getting back into a good regime. Rather than trying to run at your old pace and exhausting yourself, try combining walking and running.

Start by walking five minutes to warm up. Then, run for five minutes. Walk for five minutes, run for five minutes. Keep this up until you've spent a half hour mixing up walking and running. You'll get 30 minutes of exercise, and you'll actually spend more time running than when you gassed yourself by going too fast.

Shorten the walking intervals and lengthen the running sections until you reach the point where you are able to run for 20-30 minutes without tiring. With a good walking warm up and cool down, you can gradually build up to 30-45 minutes of continuous aerobic exercise.

After you're comfortable with running non-stop for longer periods of time, you can vary your running pace just like you alternated walking and running when you first got back into it. Walk to warm up, start jogging slowly, and then pick up your pace for a couple of minutes. Slow down to a jog again. Eventually, you'll be able to lengthen the faster sections and take shorter rest intervals. This will allow you to increase your average pace for longer periods of time, to say nothing of the heightened cardiovascular benefit of the more intense training.

Don't forget to stretch your hamstrings, lower back, quadriceps and calf muscles before, and especially after, your workout. They are going to get tighter from the running, and you need to keep them as loose as possible in order to avoid getting stiff or injured. Maintaining your flexibility will help you maintain the fluidity of your stride as well. Also, leave a day of rest in between your run days to avoid overuse injuries. Try something more low-impact on those days such as biking, spinning, elliptical machines or swimming.

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