Being fit is a way of saying a person eats well, gets a lot of physical activity (exercise), and has a healthy weight. If you're fit, your body works well, feels good, and can do all the things you want to do, like run around with your friends.

People who care (parents, doctors, teachers, and others) want to know how to help kids be more fit. Some parts of this are up to parents — such as serving healthy meals or deciding to take the family on a nature hike. But kids can take charge too when it comes to their health.

Here are 5 rules to live by, if you're a kid who wants to be fit. The trick is to follow these rules most of the time, knowing that some days (like your birthday) might call for cake and ice cream.

1. Eat a Variety of Foods

You may have a favorite food, but the best choice is to eat a variety. If you eat different foods, you're more likely to get the nutrients your body needs. Taste new foods and old ones you haven't tried for a while. Some foods, such as green veggies, may taste better the older you get.

Try for at least 5 servings of fruits and vegetables a day — 2 fruits and 3 vegetables. Here's one combination that might work for you:

• at breakfast: ½ cup (about 4 large) strawberries on your cereal
• with lunch: 6 baby carrots
• for a snack: an apple
• with dinner: ½ cup broccoli and 1 cup of salad

2. Drink Water & Milk

When you're really thirsty, water is the best thirst-quencher. And there's a reason your school cafeteria offers cartons of milk. Kids need calcium to build strong bones, and milk is a great source of this mineral. How much do kids need? If you are 4 to 8 years old, drink 2½ cups of milk a day. If you're 9 or older, aim for 3 cups of milk per day. You can mix it up by having milk, fortified soy milk, and some other calcium-rich dairy foods. Here's one combination:

• 2 cups (about half a liter) milk or soy milk
• 1 slice cheddar cheese
• ½ cup (small container) of yogurt

If you want something other than milk or water, it's OK to drink 100% juice once in a while, but no more than 1 cup a day. Don’t drink sugary drinks, like sodas, juice drinks, and sports drinks. They contain a lot of added sugar. Sugar just adds calories, not important nutrients.

3. Listen to Your Body

What does it feel like to be full? When you're eating, notice how your body feels and when your stomach feels comfortably full. Sometimes, people eat too much because they don't notice when they need to stop eating. Eating too much can make you feel uncomfortable and can lead to unhealthy weight gain.

4. Limit Screen Time

What's screen time? It's the amount of time you spend watching TV or videos, playing video games (console systems or handheld games), and using a smart phone, tablet, or computer. The more time you spend on these sitting-down activities, the less time you have for active stuff, like basketball, bike riding, and swimming. And you may not get enough sleep if you spend too much time with a screen before bed. Try to spend no more than 2 hours a day on screen time, not counting using the computer for school and educational activities.

5. Be Active

One job you have as a kid — and it's a fun one — is that you get to figure out which activities you like best. Not everyone loves baseball or soccer. Maybe your passion is karate, or kickball, or dancing. Ask your parents to help you do your favorite sports and other activities. Find ways to be active every day, like playing outside. You might even write down a list of fun stuff to do, so you can use it when your mom or dad says it's time to stop watching TV or playing computer games!

Speaking of parents, they can be a big help if you want to be a fit kid. For instance, they can stock the house with healthy foods and plan physical activities for the family. Tell your parents about these five steps you want to take and maybe you can teach them a thing or two. If you're a fit kid, why shouldn't you have a fit mom and a fit dad?