Cardiovascular Fitness - What You Need to Know About Cardio Fitness

Top view of woman running
Top view of woman running. Martin Novak/Getty Images

We often think of cardio in the context of burning calories and losing weight and, while cardio is great for that goal, it also improves your cardio fitness.

You may not think much about it, but cardio fitness measures how well your body can perform a rhythmic, dynamic activity at a moderate to high intensity for extended periods of time. 

Your cardio fitness refers to how well your heart, lungs, and organs consume, transport and use oxygen throughout your workout.

How fit you are comes down to the relationship between your cardio system, respiratory system, and skeletal system.

When all of these systems work together efficiently, you increase fitness, allowing your body to last for a longer period of time. The only way to teach these systems to work together is to practice working out consistently.

Why is this important? First, we all know the statistics flying around about the obesity epidemic in the United States. We spend way too much time sitting and doing some cardio exercise is one way to combat that.

Not only that, but cardio workouts can help you in other areas of your life. The more fit you are, the more you can handle things like keeping up with the kids, doing long days of yard work or other household projects.

How Do You Know if You're Fit?

If you're doing some kind of exercise, there's a good chance you're fit, but how exactly do you measure your cardio fitness?

One way is to simply track your own workouts. Keep track of the activity you do, how long you do it and how hard you're working.

To do that, you can use a heart rate monitor to make sure you're working in your target heart rate zone or you can keep it simple and pay attention to your rate of perceived exertion.

In that case, you use a scale of 1 to 10 to match you how feel at different levels of intensity.

So if you were working at an easy pace, that would be a Level 2 or 3. If you're sprinting all-out, that would be closer to a 10. By doing the same workouts for awhile and tracking these elements you'll see that you're able to go longer and harder as time goes on. This is probably the simplest ways to track your fitness.

On the other hand, there are much more complex tests you can take, something that often appeals to veteran exercisers, professional athletes, or people who like to compete in races.

There are lab tests you can take that cost money, but can also give you a very accurate calculation of things like your VO2 Max, which is the maximum volume of oxygen your body can consume and use. These tests can also help you figure out your Maximum Heart Rate, which is an important part of all major target heart rate zone calculations.

Treadmill Tests

There are treadmill tests that can determine your cardiovascular fitness. These are usually administered by a pro at a gym or a lab, and may involve working up to a very high intensity.

The Graded Exercise Test involves a long series of intervals on the treadmill while monitoring blood pressure and heart rhythms.

 The Bruce Protocol Test also involves working on a treadmill while your heart rate, blood pressure, and perceived exertion are monitored. Both of these are tests you can't really do on your own.

These may be accurate, but most of us don't have access to these tests in real life. That's fine because there are other tests you can do on your own that don't involve EKG machines or blood pressure monitors.

Testing Your Cardio Fitness

If you're an athlete or competing at a high level, you may want to take one of those high intensity treadmill tests. But, if you want a simpler method to test your fitness, you're in luck.

Below are some of the most popular ways to test your cardio fitness on your own. 

Try taking one or both of these tests every few weeks to see how you're doing. It can be motivating when you see those numbers change right in front of your eyes. Having something tangible to look at is often more powerful than just knowing it in your mind.

The 3-Minute Step Test

The 3-Minute Step Test is one of the simplest methods, that is if you have a step. With this test, you use a 12-inch step and a metronome or a stopwatch. If you have a smartphone, you can easily find a free metronome app out there.

You step up and down to the metronome for 3 minutes, sit down and take your heart rate for one full minute, counting each beat. It's great to use a heart rate monitor here so you can actually see each beat.

Check the chart below for your ratings:

Ratings for Women Based on Age

 18-25 26-3536-4546-5556-6565+
Above Average96-10295-101100-104104-110106-111104-111
Below Average113-120113-119115-120120-124119-127123-126
Very Poor135-169134-171137-169137-171141-174135-155


Ratings for Men Based on Age

 18-25 26-3536-4546-5556-6565+
Above Average88-9388-9488-9595-10197-10094-102
Below Average102-107104-110108-113113-119111-117114-118
Very Poor124-157126-161130-163131-159131-154130-151


The Rockport Walk Test

The Rockport Walk Test is even simpler than the others. For this, you warm up and then walk a mile as fast as you can, either on the treadmill or outside. You record your heart rate and workout time and enter your results into this Rockport One Mile Walk Calculator to see where you rank.

This is a great test to do on a track so you know exactly how far you're going.

How to Improve Your Cardio Fitness

When it comes to improving your cardio fitness, that's simple, if not always easy to do. The way to get better at cardio is to do it on a regular basis. Consistency is how you build endurance and fitness and there are a variety of ways to do that, including:

  • Steady State Training: This type of cardio involves running, walking, getting on the elliptical or doing some other cardio activity at a moderate pace for 20 or more minutes. With this, you build endurance in your entire body as well as your heart and lungs to be able to last longer during cardio. Start with what you can manage, even if it's only a few minutes. Each workout, add on a few minutes so you're going longer and longer, keeping that moderate pace. Once you can workout continuously for 30 minutes, then you can start working on different levels of intensity.
  • Interval Training: This involves going fast/hard and then backing off to recover for the duration of the workout. This can actually help you build endurance more quickly than steady state training, especially if you work way out of your comfort zone (which is about a Level 9 on this Perceived Exertion Scale). Doing an interval workout 1 or 2 times a week can boost your endurance and your calorie-burn. And, even better, these works are often shorter and fit well into a busy schedule.
  • Mix and Match: One of the best ways to boost fitness is mixing both steady state and interval workouts throughout the week. Too much interval training can cause injury or overtraining and too much steady state can be boring. If you're a beginner, start 3 or 4 workouts a week and focus on 2 steady state workouts such as this Basic Endurance Workout and one interval routine, like this Beginner Interval Workout. For more, check out this Sample Cardio Workout Schedule.

Being fit is all about being able to handle everything in your life with endurance and energy. Working on your cardio fitness each week is a great way to make all your other activities seem easier.


Riebe D, Ehrman JK, Liguori G, Magal M. ACSMs guidelines for exercise testing and prescription. Philadelphia: Wolters Kluwer; 2018.​

Continue Reading