You might have some idea of how fit you are. But knowing for sure can help you set good fitness goals, see your progress and stay motivated. Once you know your starting point, you can plan where you want to go. Get started with the simple tests below.

Most often, measures of fitness involve these key areas:

• Aerobic fitness, which involves how well the heart uses oxygen.
• Muscle strength and endurance, which involve how hard and long muscles can work.
• Flexibility, which is how able joints are to move through their full range of motion.
• Body composition, which involves how much fat, bone and muscle are in the body.

To do your assessment, you need:

• A stopwatch or a watch that can measure seconds.
• A cloth measuring tape.
• A scale.
• Someone to help you record your scores and count how many times you repeat something.

You'll also need a pencil or pen and paper to record your scores as you finish each part of the test. You can record your scores in a notebook or journal. Or you can save them in a spreadsheet or another electronic format.

The target heart rate zone is a heart rate range that gives your heart and lungs a good workout. This zone ranges from 50% to 85% of the maximum heart rate (MHR) for your age. Aim for 50% to 70% of MHR when you do moderately intense activities and 70% to 85% of MHR when you do vigorous activities.

You can use the target heart rate zone as a guide to see how hard you're exercising. It's okay if you don't reach your target zone. Any activity is good for your health. If you're on the lower end of your target heart rate zone, you can try to increase your effort little by little to get more from your workout.

If you exercise regularly, you can stop briefly to check your heart rate at times during an aerobic workout. If you don't exercise regularly, you can do a simple test by checking your heart rate after a brisk 10-minute walk.

Another way to test your aerobic fitness is to time yourself on a 1.5-mile (2.4-kilometer) run or jog. The following times show a good fitness level based on age and sex. A lower time most often means better aerobic fitness. A higher time suggests a need to do better.

If the size of your waist, called the circumference, is greater than your hips, you carry more weight above the hips. This means you have a higher risk of heart disease and type 2 diabetes.

The risk is even greater for women with waist sizes of 35 inches (89 centimeters) or more. For men, the risk is higher with waist sizes of 40 inches (102 centimeters) or more.

With a cloth measuring tape, measure your waist just above the hipbones.

Your body mass index (BMI) shows whether you have a healthy amount of body fat. You can find your BMI with a BMI table or online calculator.

To do the math yourself, divide your weight in pounds by your height in inches squared. Then multiply by 703. Or divide your weight in kilograms by your height in meters squared. To get your height in meters, divide your height in centimeters by 100.

The following shows what your BMI results mean.

The results of these fitness tests can help you set goals for staying active and getting more fit. For most healthy adults, the Department of Health and Human Services recommends these exercise guidelines:

• Aerobic activity. Get at least 150 minutes of moderate aerobic activity. Or get at least 75 minutes of vigorous aerobic activity a week. You can also get an equal mix of the two types. Aim to exercise most days of the week.
• Strength training. Do strength training exercises for all major muscle groups at least two times a week. One set of each exercise is enough for health and fitness benefits. Use a weight or resistance level heavy enough to tire your muscles after about 12 to 15 repetitions.

Moderate aerobic activity includes:

• Walking at a good pace.
• Water aerobics.
• Bicycling slower than 10 miles an hour on mostly level ground.
• Pushing a lawn mower, gardening or doing home repair.

Vigorous aerobic activity includes:

• Running.
• Swimming laps.
• Fast bicycling or biking hills.
• Jumping rope.
• Playing singles tennis.

Muscle-strengthening exercises include:

• Lifting weights or using resistance bands.
• Calisthenics that use body weight for resistance.
• Heavy gardening or yardwork.

Keep track of your progress in building fitness. Take the same measurements about six weeks after you begin an exercise program. Then take them once in a while.

Each time you repeat your tests, take pride in your progress. Then increase your fitness goals. Share your results with your healthcare professional or personal trainer for more guidance.