You can do your children a great favor by working a lot of physical activities into their day, and helping them make a habit of good health. Create fun activities for the entire family to do together; it makes for great bonding and quality time spent together as a family too:
1. Get into the bicycling habit. Make sure that your children learn how to cycle as soon as possible or are able to accompany others with their little trainer wheels. 
You can go grocery shopping together, you can go for picnics close by to the home or other outings, and basically do a lot of stuff leaving the car at home.
The child gets into the habit of using a cycle rather than asking his or her parent to drive them; thereby becoming more self reliant and physically active.
2. Organize daily outdoor time: A number of activities such as gardening, mending, doing small carpentry jobs, or other chores and fixing around the house can be done together by a couple of family members.
Whether it’s just tossing a ball in the yard, or playing Frisbee or putting up a hoop by the garage for basketball, be creative and make sure that everyone in the house is interested in getting some fresh air and activity each day.
3. Get a dog: Psychologists have long said that those people that have pets are healthier. Also it is better for children to grow up around animals.
Also having a dog makes it compulsory that you have to take the pooch for a walk once or twice at least in a day. Assign this duty to a child or children by turn or better still go with them for a good brisk walk.
4. Pick up a sporting habit: Get the child interested in a sport such as tennis, badminton, swimming, or any other that requires fairly strenuous physical activity. Sport has its own rewards and will keep the child interested and committed to it.
5. Make activity a reward rather than food: Suppose you want to hold out a blandishment for your child who has some tests coming up. You want to encourage them and also offer a reward: “you get this if you do well”.
Now let that reward not be food connected. So rather than tell the child you can have a treat at X favorite restaurant tell them if you do well we can go for a particular activity such as a skating outing for the family, or going rock climbing or for a tramp through the woods as a picnic etc.
