Cardiorespiratory fitness is not measured by how many 45-pound weight plates you can stick on a squat rack, or whether you can bench press 315 pounds. It can't be achieved by hanging out in the weight room.

If you want total body fitness, you'll have to ride the stationary bike or finally give the elliptical machine a try.

The American Council on Exercise describes cardiorespiratory fitness as the health and function of the heart, lungs and circulatory system, and it is related to the body's ability to persist or sustain activity for prolonged periods of time.

Translated, this means endurance, not strength.

Because this type of fitness demonstrates your lungs' ability to exchange oxygen and carbon dioxide with the blood, cardiorespiratory fitness serves as the basis for other fitness programs.

Individuals with adequate cardiorespiratory fitness will discover they have more stamina, which results in less fatigue and fewer risks of certain types of injuries.

Basically, if you're in good cardio shape, you'll be able to participate in other activities, such as team sports and weight training, for a longer time before feeling worn out.

The ability to be active longer is only one of the numerous benefits that accompany cardiorespiratory fitness. Getting your heart and lungs in shape will reduce the risk for diseases such as obesity, hypertension (high blood pressure) and diabetes.

For gradual improvements of cardiorespiratory fitness and decreased body fat percentage, it is important to exercise at least three days per week with no more than two days rest in between workouts.

The American College of Sports Medicine recommends exercising three to five days per week, for 30 - 60 minutes each day.

To keep cardiorespiratory workouts challenging, work to maintain variety in exercises chosen. Gradually increasing the number of minutes of exercise during the conditioning period is also beneficial, as well as gradually escalating exercise intensity by increasing resistance or incline.

If you're a beginner with lower cardiorespiratory fitness, get started with 10 - 20 minutes of aerobic conditioning.

Any activity that continuously uses large muscle groups for at least 20 minutes or longer targets your cardiovascular and respiratory systems.

Those with average classification should be conditioning 15 - 45 minutes, while those with high levels should be following the guidelines of 30 - 60 minutes.

Activities like running, walking, bicycling, swimming, rowing and stair-climbing will place an extra demand on the cardiovascular and respiratory systems to achieve and improve your cardiorespiratory endurance.

Melissa Haug is a senior in public health nutrition and dietetics and a nutrition consultant and American Council on Exercise certified personal trainer at Peters Recreational Complex. Please send comments to sports@spub.ksu.edu