The National Association for Sport and Physical Education has set these exercise guidelines for healthy toddlers:

* Toddlers should get at least 30 minutes of daily structured physical activity (organized sports, a game of hide and seek, a walk down the block);

* Toddlers should get at least an hour and up to several hours of daily, unstructured physical activity (meaning they are amusing themselves, and mom is not directing or organizing the activity);

* Toddlers should not be still or sedentary (such as in front of the TV or playing a video game) for more than 60 minutes at a time, except when sleeping.

-Michael
References :
http://www.free-toddlers-activity-and-discipline-guide.com/toddlers-activity-parent-child-development.html

Hope you find something to keep your little one busy and active!
Maybe everyday for a few minutes you could do some exercises with her and do things like 5 jumping jacks, 5 sit ups, etc and then reward her with a peice of fruit or somthing.
References :
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the rollrollroll
Put a blanket on the floor and have your toddler lie down on her back at one end and then roll to the other side of the blanket. You might have to help at first or demonstrate. Kids love to watch adults and then try to copy what they do! Roll to one side and then to the other! Or you can both start on the ends and roll toward each other so that you meet in the middle! Remember to count each time she rolls over and celebrate with some hi-5’s when she does it!

here another one’

Find a place on the rug or floor and put some masking tape down in the outline of a square. Next, have your toddler stand just outside the square and then tell her to jump inside the square! Then have her jump outside the square from standing inside. Again, start by showing her how to jump inside and jump outside ( or use a stuffed animal to show her how to do it.)

If you have a yoga mat or exercise mat, roll it out onto the floor/rug. Then have your toddler lie down on his back with his knees bent and his feet on the mat. Then have him stomp his feet up and down on the mat to make some noise. You can also put down some paper from a brown paper grocery bag so that your toddler can make more noise with his feet. Count to ten has he stomps up and down and celebrate with some tickling and giggles when you get to 10!

Each time you start some exercises, tell your toddler that it is "Exercise Time!" Soon, you’ll see that your toddler will ask to do exercises because they are so much fun! Start each activity/exercise by showing your toddler what you are going to do. Play some fun music while you do the exercises. Remember that the more fun you are having the more interested your toddler will be in what you are doing.)
References :

Races to clean up are good for you and her. Pick an item, like clothes or shoes (dog toys are big in our house), and go around picking them up as quick as you can. When your done see how many you each have, and declare a winner.

If you have a yard, take a ball out there and let them kick it around. They’ll get exercise chasing the ball and have fun.
Dancing can be great exercise and a lot of fun too. Going for walks is always good exercise.

As long as she isn’t like a bump on a log, she probably gets enough exercise. Most toddlers are constantly moving and exploring. Just walking is building their muscles. Make sure she doesn’t watch more than a half hour to an hour of tv a day, this will encourage her to get up and move.
Hope that helps
References :