What is the best 10-minute exercise I can do daily to keep myself fit?

1. When you go outside to pick up your morning newspaper, take a brisk5-minute power walk up the street in one direction and back in the other. 

2. If you're housebound caring for a sick child or grandchild, hop on an exercise bike or do a treadmill workout while your ailing loved one naps.

3. Try5 to minutes of jumping jacks. (A-pound woman can burn calories in one-minute session.)

4. Cooking dinner? Do standing push-ups while you wait for a pot to boil. Stand about an arm's length from the kitchen counter, and push your arms against the counter. Push in and out to get toned arms and shoulders.

5. After dinner, go outside and play tag or shoot baskets with your kids and their friends.

First question I would ask would be, "why ten minutes"?