In a word: GRADUALLY. One of the biggest fitness mistakes people make is expecting to achieve too much too soon. Take an incremental approach to increasing your workout challenge, and you'll revel in the results.

Here's a general plan:

  • Reach the point where you can walk at a brisk pace for 30 minutes easily and comfortably. (If you're not at that point yet, don't worry. Simply add on a couple minutes or increase your speed slightly every few workouts, until 30 minutes of brisk walking feels good.)
  • Start introducing 30-second "micro-jogs" into your walk. After the 30 seconds, resume walking until you've recovered (caught your breath, feel re-energized), then jog for another 30 seconds, recover by walking, etc.
  • Gradually increase the length of each jogging interval to 1 minute, 2 minutes, and so on. Before long, the jogging portion of your workout will be longer than the walking part. And beyond that, you'll be jogging start-to-finish.

Of course, this step-wise plan -- often referred to as "interval training" by fitness exerts -- will work if you decide you want to advance from jogging to running.