What it measures: Cardiorespiratory fitness.

 Why it's important: "High cardiorespiratory fitness levels are associated with fewer health problems," says Steven Farrell. That includes strokes, heart attacks, and breast and colon cancers.

 What you need: Stopwatch or watch with a second hand.

 How to do it: Find a place to walk an uninterrupted mile―a treadmill; four laps of a standard, quarter-mile school track; a flat, quiet road that you've clocked with your car's odometer. Walk as fast as you can, maintaining a steady pace. Keep your shoulders back, your abdominal muscles slightly contracted, and your posture upright. As soon as you finish, record your time to the nearest second. Keep walking for a few minutes, but slow your pace to cool down.

Your Score: One-Mile Timed Walk*

(In minutes and seconds)

 Time for Women Under Age 40
Well above average: 13:30 or less
Above average:13:31 to 16:00
Average: 16:01 to 18:30
Below average: 18:31 to 20:00
Well below average: 20:01 or more

 Time for Women Age 40 and Over
Well above average: 14:30 or less
Above average: 14:31 to 17:00
Average: 17:01 to 19:30
Below average: 19:31 to 22:00
Well below average: 22:01 or more

*Adapted from the Cooper Institute and used by the American Council on Exercise.