Understanding and Improving Your Cardiovascular Fitness

Measure and Track Your Cardio Fitness

woman running on a path with buildings in the background

Verywell / Ryan Kelly

Cardio fitness measures how well your body can perform a rhythmic, dynamic activity at a moderate to high intensity for extended periods of time. While cardio exercise is great for burning calories and helping with healthy weight balance, it also improves your cardiovascular fitness.

Cardio workouts are one tool in the battle against inactivity and obesity, but the benefits extend throughout 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.

What Is Cardio Fitness

Your cardio fitness refers to how well your heart, lungs, and organs consume, transport, and use oxygen throughout your workout. Your overall fitness depends on the relationship between your cardiovascular system, respiratory system, and skeletal system.

When all of these systems work together efficiently, you increase fitness. The only way to teach these systems to work together is to practice working out consistently.

Measuring Cardio Fitness

To know your level of fitness, you need to measure it. 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. You can then look for trends.

You can use a heart rate monitor to make sure you're working in your target heart rate zone or you can pay attention to your rate of perceived exertion. Use a scale of 1 to 10 to match you how you feel at different levels of intensity. Exercising at an easy pace 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 a while and tracking these elements, you'll see that you're able to go longer and harder as time goes on.

More complex tests appeal to veteran exercisers, professional athletes, or people who like to compete in races. Tests can give you an 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.

Some fitness bands and smartwatches that measure resting and exercise heart rates have fitness tests and scores built-in. For example, Fitbit models with heart rate monitoring give a cardio fitness score. Garmin GPS sports watches and some of their fitness bands will report VO2 max.

You can do a three-minute step test or a Rockport walk test without any complex equipment. 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. Having something tangible to look at is often more powerful than just knowing it in your mind.

We've tried, tested, and reviewed the best heart rate monitors. If you're in the market for a heart rate monitor, explore which option may be best for you.

Treadmill Tests

Treadmill tests can determine your cardiovascular fitness. These are usually administered by a professional 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 are accurate but may be costly. There are other tests you can do on your own that don't involve EKG machines or blood pressure monitors.

The 3-Minute Step Test

The three-minute step test is one of the simplest methods. With this test, you use a 12-inch step and a metronome, stopwatch, or metronome app for your mobile phone.

You step up and down to the metronome for three minutes, then sit down and take your heart rate for one full minute, counting each beat. It's great to use a heart rate monitor or heart rate app so you can actually see each beat. Check the charts below for your ratings.

Ratings for Women Based on Age

18-25 26-35 36-45 46-55 56-65 65+
Excellent 52-81 58-80 51-84 63-91 60-92 70-92
Good 85-93 85-92 89-96 95-101 97-103 96-101
Above Average 96-102 95-101 100-104 104-110 106-111 104-111
Average 104-110 104-110 107-112 113-118 116-121 116-121
Below Average 113-120 113-119 115-120 120-124 119-127 123-126
Poor 122-131 122-129 124-132 126-132 129-135 128-133
Very Poor 135-169 134-171 137-169 137-171 141-174 135-155

Ratings for Men Based on Age

18-25 26-35 36-45 46-55 56-65 65+
Excellent 50-76 51-76 49-76 56-82 60-77 59-81
Good 79-84 79-85 80-88 97-93 86-94 87-92
Above Average 88-93 88-94 88-95 95-101 97-100 94-102
Average 95-100 96-102 100-105 103-111 103-109 104-110
Below Average 102-107 104-110 108-113 113-119 111-117 114-118
Poor 111-119 114-121 116-124 121-126 119-128 121-126
Very Poor 124-157 126-161 130-163 131-159 131-154 130-151

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 a Rockport 1-mile walk calculator to see where you rank. It's best to do this test on a track so you know exactly how far you're going.

How to Improve Cardio Fitness

Improving your cardio fitness is 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 the following.

Steady-State Training

This type of cardio involves running, walking, using the elliptical, or doing some other cardio activity, such as riding a recumbent exercise bike or using a weighted hula hoop, at a moderate pace for 20 or more minutes. You build endurance in your entire body as well as your heart and lungs to be able to last longer during cardio as it helps reduce blood pressure and increases your heart and lungs' ability to transport oxygen rich blood through your body. 

Start with what you can manage, even if it's less than 20 minutes. Add a few minutes to each workout so you're going longer and longer while keeping a moderate pace. Once you can work out continuously for 30 minutes you can start working on different levels of intensity.

Interval Training

This involves going fast or hard and then backing off to recover, repeating these intervals for the duration of the workout. Interval training can help you build endurance more quickly than steady state training, especially if you exert yourself far above your comfort zone, at about a level 9 on the perceived exertion scale.

Doing an interval workout one or two times a week can boost your endurance and your calorie burn. Even better, these workouts are often shorter and fit 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 three or four workouts a week and focus on two steady-state workouts such as a basic endurance workout and one interval routine, such as a beginner interval workout.

Safety and Precautions

When building your cardiovascular fitness, ensure you do not overtrain. This can happen when you perform too much exercise, aren't recovering between workouts, are not eating enough, are not getting enough sleep, or any combination of these factors.

Remember to take rest days or active rest days that include lighter forms of activity such as walking. Rest will help your recovery so you're ready for the next training session and less likely to become injured. Overtraining is difficult to recover from once it sets in, so avoiding it is best.

Signs you may be close to or entering overtraining include feeling agitated, moody, trouble sleeping, loss of appetite, depression or stress. Back off and take at least a week off of any intense or prolonged training.

A Word From Verywell

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. Blending both higher intensity and steady state cardio is a tried-and-true strategy for building your cardiovascular fitness levels without overtraining. Remember to take rest days and refuel and hydrate yourself well for the best chances of proper recovery.

6 Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  2. Foster C, Farland CV, Guidotti F, et al. The effects of high intensity interval training vs steady state training on aerobic and anaerobic capacityJ Sports Sci Med. 2015;14(4):747-755.

  3. Cardoos N. Overtraining syndromeCurr Sports Med Reports. 2015;14(3):157-158. doi:10.1249/JSR.0000000000000145

  4. McCall P. 8 reasons to take a rest day. American Council on Exercise.

  5. Grandou C, Wallace L, Coutts A, Bell L, Impellizzeri F. Symptoms of overtraining in resistance exercise: international cross-sectional surveyInt J Sports Physiol Perform. 2019;16(1):80-9. doi:10.1123/ijspp.2019-0825

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Additional Reading
  • Riebe D, Ehrman JK, Liguori G, Magal M. ACSMs Guidelines for Exercise Testing and Prescription. Philadelphia: Wolters Kluwer; 2017.

By Paige Waehner, CPT
Paige Waehner is a certified personal trainer, author of the "Guide to Become a Personal Trainer," and co-author of "The Buzz on Exercise & Fitness."