Cardiovascular fitness is the ability to handle aerobically exercise of differing durations. Improving your cardiovascular fitness can help increasing the efficiency of your heart, lungs, and blood vessels. The easier it is to pump blood through your body, the less taxing it is on your heart. This is important, especially since the leading cause of death in the United States is heart disease.
Through cardio training, your heart’s strength, your blood vessels elasticity, and the efficiency of your blood to carry oxygen will improve.
These will give you major health benefits.
Regular aerobic training will also aid you in maintaining a healthy body composition. Aerobic (running) and anaerobic (lifting) exercise, especially at higher intensities, contributes to a high levels of calories being burned. The fat you store on your body is reserved for periods of prolonged or intense activity. Training the cardiovascular system through high-intensity intervals increases the activity of certain hormones, such as testosterone and growth hormone, which start the fat burning process.
While low-intensity, steady-state cardio burns a higher percentage of fat, high intensity exercise results in greater total calorie burn, and speeds up the enzymes associated with burning fat.
You need both high intensity and low intensity cardio to get the best results.
Finally, having greater cardiovascular fitness means you can confidently complete activities that have a cardiovascular demand, such as climbing stairs, hiking, biking, swimming, and, believe it or not, even strength training.
Being able to move through your day without feeling tired can make a huge difference in your quality of life and confidence. And, a good cardiovascular base allows you to train harder during strength sessions without feeling fatigued.
It is very common to perform cardiovascular exercise as your ONLY form of exercise. For example, a typical marathon runner would have a very high level of cardiovascular fitness, but they may be muscularly weak due to a lack of strength training, and stiff due to repetitively working the same muscles on a single plane of motion.
Remember the four pillars of Fitness: Strength, Cardiovascular Fitness, Mobility, and Body Composition.
You want to have balance.
In the example above, the runner has developed a high degree of cardiovascular fitness, but neglected the 3 other pillars. As a result, they are protected from heart disease, and can handle aerobically taxing situations, but are still susceptible to the consequences of having poor strength, mobility, and body composition.
The lack of strength training, coupled with only moving the joints in one repetitive motion, can exacerbate joint degradation and lead to overuse injuries, poor posture, and immobility. If an individual could run a marathon, but was unable to confidently pick up 225 lbs off the floor, would you consider them as being physically fit?
Could they complete a variety of physical demands, and come out uninjured?
The runner will probably escape developing cardiovascular disease later in life, but their poor mobility and lack of strength may lead to needing a knee replacement, or they become more susceptible to falling due to a lack of muscle mass.
It is crucial to understand that cardiovascular exercise is only one component of being a healthy, fit, and capable person!
So make sure to take a balanced approach to fitness. Cardio is important, especially if you are typically only a weight lifter…. But the opposite is true as well.
Seek balance in your training.

Author's Bio: 

BIO: Coach David Brett
As a fitness enthusiast, I have dedicated my life to helping others learn more about fitness and nutrition.
Through my years of experience, I’ve learned what works – and what doesn’t.
Check out my website, brettsfitnesstips.com, and take your fitness up a notch!