If you want to be truly fit, work to improve these five main areas of physical fitness:

1. Cardiovascular endurance. This is the ability of your heart and lungs to work efficiently at a moderate intensity over a long period of time. To improve in this area, perform cardiovascular activities such as brisk walking, bicycling, running, lap swimming and aerobic dancing three to six times per week for 20-60 minutes per session.
2. Muscular endurance. This is the ability of your muscles to perform a particular exercise for a long period of time. Typically, such exercises are done without weights or with light weights. Examples are: push-ups, abdominal crunches, dips, lunges and squats. To improve in this area, perform the exercises three or four times per week for 20-30 minutes.
3. Muscular strength. This is the ability of your muscles to lift a moderate to heavy amount of weight with control. Remember, muscular strength will decrease with age unless the muscles are exercised regularly and efficiently. Choose a total body workout that includes exercises for the upper back, chest, shoulders, biceps, triceps, lower back, abdominals, buttocks, quadriceps, and hamstrings. For each exercise, perform 2-3 sets of 8-12 repetitions. Make sure that the weight is heavy enough to challenge the muscles. If you find that you can lift the weight more than twelve times, then the weight is too light to really challenge your muscles. Perform the total body workout 2-3 times per week.
4. Flexibility. This is the ability of your joints to move through a full range of motion and the ability of your muscles to relax, stretch and lengthen. Good flexibility is important to balance muscular strength and prevent stiffness and soreness. Perform stretches for all of the muscles that you work in your total body strength workout 2-3 times per week. Remember to relax and stretch slowly, holding each stretch for at least 30 seconds. There are some good books available that teach stretches and stretching techniques. Also, consider joining a yoga or stretching class.
5. Body fat percentage. This is the percentage of your total body weight that is made up of stored body fat. Your body fat can be tested using various methods such the skinfold caliper method or bioelectrical impedance. Such tests can usually be obtained through health clubs or a referral from your physician. Remember that body fat percentage is a better measure of fitness than body weight because it is possible to be thin but still overfat. Recommended body fat percentages are: Men - 13-18% Women - 19-24%. To reduce your body fat, exercise regularly (as outlined above) and follow a healthy diet that is low in calories, added fat and added sugar.