Everything You Need to Know About Cardio

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The word "cardio" is probably one of the first words you hear when you first start an exercise program. You know that cardio is an essential component of any workout, whether you want to lose weight, get fit, or just be healthier. Health authorities recommend 150 minutes of cardio exercise per week to reduce health risks.

If you want to lose a substantial amount of weight (more than 5% of body weight) and/or keep it off, you may have to do more than 300 minutes of moderate-intensity physical activity a week and that doesn't even include strength training. Getting a deeper understanding of cardio exercise may be what you need to get motivated to do it a little more often.

Cardio Exercise Definition

Cardio exercise simply means that you're doing a rhythmic activity that raises your heart rate into your target heart rate zone, the zone where you'll burn the most fat and calories.

Even bouts (or episodes) as short as 10 minutes count towards your weekly cardio exercise minutes. According to the 2018 Physical Activity Guidelines Advisory Committee, "episodes of any length contribute to the health benefits associated with the accumulated volume of physical activity."

Benefits of Cardio Exercise

When you realize just how much cardio exercise can do for you, you may want to do some right now. There are very few activities you can do for a short period of time that have this many benefits.

Some of the known benefits of cardio include:

  • Burns fat and calories for weight loss
  • Enhances sleep quality
  • Expands lung capacity
  • Improves sex life
  • Increases bone density (weight-bearing cardio exercise)
  • Lowers stress
  • Promotes feeling good, and can even provide temporary relief from depression and anxiety
  • Provides more confidence in how you look and feel
  • Reduces the risk of heart attack, high cholesterol, high blood pressure, diabetes, and some forms of cancer
  • Sets a good example for your family
  • Strengthens the heart so that it doesn't have to work as hard to pump blood

The great thing about cardio is that you don't have to work out for an hour at a high-intensity to get the benefits. Even a little goes a long way. A 15-minute walk outside can boost your mood and help lower blood pressure.

Don't feel like you have to have a lot of time and energy for cardio. Doing a little each day is better than doing nothing at all. With all the benefits laid out for you, it's time for the next step which covers exactly how to choose your cardio exercise.

Choosing a Cardio Exercise

Your first step in setting up a program is to figure out what kind of activities you'd like to do. The trick is to think about what's accessible to you, what fits your personality, and what you'd feel comfortable fitting into your life. If you like to go outdoors, running, cycling, or walking are all good choices.

Just about any activity will work, as long as it involves a movement that gets your heart rate into your heart rate zone. Walking is always an excellent choice. It's something most of us can do on a regular basis and you don't need fancy equipment.

If you prefer going to the gym, you have access to many more options in the form of machines like stationary bikes, elliptical trainers, treadmills, rowing machines, climbers, the pool, and more.

For the home exerciser, you can, of course, buy your own treadmill or elliptical trainer, but there are other great options like:

  • Exercise videos
  • Fitness apps
  • Home cardio exercises like jumping rope, jumping jacks, jogging in place, burpees, and more
  • Online workouts

You have so many choices but, the trouble is, you may not even know what you like yet. You may have to try several different activities before you find one that works for you. This is the experiment we all have to take part in and it can be hit or miss so don't be afraid to try something and, if it doesn't work, move on to something else.

Here are some tips to keep in mind:

  • Be flexible. Don't be afraid to branch out. The nice thing about cardio is that you can choose any activity that raises your heart rate. You don't have to do the same workout every session, or every week. Changing up your cardio is easy. Try different things to discover more activities you enjoy.
  • Choose something you can see yourself doing regularly. To meet the exercise recommendations, you need to do cardio 3 days per week. Make it easier to be consistent by choosing an activity that is convenient for you to do that often, at least until you've formed the habit.
  • Do something you enjoy (or at least something you can tolerate). If you hate gym workouts, don't force yourself onto a treadmill. Walk, jog, or bike outdoors to enjoy the scenery. If you like socializing, consider sports, group fitness, working out with a friend, or a walking club.
  • Keep it simple. If you're confused about what to do, start with the basics. You need at least 20 minutes for the body to get going, so start there. Get out your calendar, find 20 minutes of time on 3 different days, and do something such as walking, running, going to the gym, vigorous yard work. Make cardio a habit first and work on your time and intensity later.
  • There is no 'best' cardio exercise. Just because your friend says running is the best doesn't mean you have to do it, especially if running makes you feel like your entire body is falling apart. Anything that gets your heart rate up fits the bill, even vigorous chores like raking leaves or washing the car.

How Long Should a Cardio Workout Last?

After you choose what to do, the most important element of your workout will now be how long you do it. You should work on duration before you work on anything else like doing high-intensity workouts; it takes time to build up the endurance for continuous exercise.

The guidelines suggest anywhere from 20 to 60 minutes of cardio to be healthy, lose weight, and get fit, depending on the types of workouts you do. That's fine, but you don't want to start with an hour of exercise. That's just too much for anyone if you haven't exercised for a while (or ever).

Beginner Workouts

To start, choose an accessible exercise like walking or a treadmill, and start with about 10–20 minutes of brisk walking at a moderate-intensity. That means you're just out of your comfort zone, at around a Level 5 or 6 on a perceived exertion scale of zero to 10, where sitting is zero and the highest level of effort possible is 10.

Beginner workout options:

To determine how long you should workout, consider the following:

  • Add small bursts of cardio throughout the day. Try climbing the stairs or speed walking.
  • Do all those things you know you should be doing. Take the stairs, walk more, stop driving around looking for that front row parking space, etc.
  • Do something—anything. If you think 5 minutes isn't enough time to work out, you couldn't be more wrong. Whether it's 5 minutes, 10 minutes, or 60 minutes, every single minute counts.
  • Make the time. People who work out don't have more time than people who don't. They've just practiced making exercise a priority. Scheduling your workouts and treating them like any other appointment you wouldn't miss may help you stick to your program.
  • Pay someone to make you exercise. Finding a good personal trainer can make a big difference when it comes to motivation and reaching your goals.
  • Take intensity into account. The harder you work, the shorter your workouts should be. So, if you're doing Tabata training or some other kind of high-intensity interval training, your workout may only be 10–20 minutes long. If you're doing a slower, steady-state workout, you can work out longer, maybe 30–60 minutes.
  • You don't have to do it all at once. You can absolutely split your workouts into smaller workouts throughout the day. Try three 10-minute walks as a good start.

Frequency of Cardio Workouts

The short, non-scientific answer to how often to do cardio workouts is to do more than you probably think you should and more than you really want to or have the time for.

The longer answer is that it depends on your fitness level, schedule, and goals. If you want to be healthy and aren't worried about losing weight, getting in 20–30 minutes of moderate activity every day can do you some good. But, for weight loss, it's a whole other story.

And it's not just about frequency. It's about intensity as well. If you only do moderate workouts, you can probably workout every day. But, if you do high-intensity interval training, you may need more rest days in between workout days. The bottom line is that it's better to have a mixture of the two so that you're working different energy systems and giving your body something different to do so you don't burn out.

Guidelines for Cardio Frequency

The frequency of your workouts will depend on your fitness level and your schedule. The general guidelines are:

  • For general health, try moderately-intense cardio 30 minutes a day, 5 days a week, or vigorously-intense cardio for 20 minutes a day, 3 days a week. You can also do a mixture.
  • For weight loss and/or to avoid regaining weight, you may need to do more than 300 minutes of moderate-intensity activity a week to meet your goals.
  • To maintain a healthy body weight, you need about 150 to 300 minutes of moderate-intensity activity a week.

When Life Gets in the Way

What happens if you can't follow the guidelines? If you're still working on building the endurance and conditioning, it may take a few weeks to work your way up to more frequent exercise.

If it's a busy schedule that stands in your way or other obstacles, do your best to work out as many days as you can try shorter, more intense circuit training workouts to make the most out of the time you do have.

10-minute time-saver workout ideas:

Keep in mind that if you can't follow the guidelines because of your busy schedule, you may have trouble reaching your weight loss goals.

If you can't do the work required to reach your goals, you may have to change your lifestyle or, if that isn't working, change your goal to fit where you are in your exercise or weight loss experience.

Cardio Intensity

Once you've gotten used to exercising (and are up to 30 minutes of continuous movement) you can start working on your intensity. How hard you work is a crucial factor in your workout because of:

  • Calorie burn: Intensity is directly related to how many calories you burn.
  • Ease of monitoring: A heart rate monitor or the perceived exertion scale makes it easy to monitor your exercise intensity.
  • Time savings: Raising your intensity burns more calories when you're short on time.
  • Variation: Intensity is an easy part of your workout to change without having to find a new exercise to do.

How Hard Should You Work?

Your best exercise intensity level depends on several factors including your fitness level and your goals. There are three different levels of intensity you can focus on during your workouts, and you can even incorporate all of these levels into the same workout:

  • High-Intensity Cardio: This falls between 70% and 85% of your maximum heart rate (MHR), or a 7 to 8 on the perceived exertion scale. This level feels challenging and leaves you too breathless to talk much. If you're a beginner, try beginner interval training to work harder for shorter periods of time.
  • Moderate-Intensity Cardio: Moderate intensity falls between 50% and 70% of your MHR (a level 5 to 6 on the perceived exertion scale). The U.S. Department of Health and Human Services often recommends this level of intensity in its Physical Activity Guidelines. This is the level you typically want to shoot for during your workouts.
  • Low-Intensity Cardio: This type of exercise is considered to be below 50% of your MHR, or about a level 3 to 4 on the perceived exertion scale. This is a good level to work at during your warm-ups or when you're squeezing in other activities, like walking, throughout the day.

Keep in mind that your target heart rate calculation isn't 100% accurate so you might want to use a combination of perceived exertion and your heart rate to find a range that works for you.

Doing too much cardio is a no-no and can actually backfire. There is a point of diminishing returns, so keep it reasonable (3–6 days per week, depending on your fitness level), vary your intensity, and don't forget to take rest days when needed.

A Word From Verywell

Whatever you do, remember to keep it simple. Just start somewhere and make it a goal to do something every day, even if it's just a 5-minute walk. Try doing it at the same time every day and schedule it on your calendar. The more you practice the easier it gets.

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Article 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.
  1. Piercy KL, Troiano RP, Ballard RM, et al. The Physical Activity Guidelines for Americans. JAMA. 2018;320(19):2020-2028. doi:10.1001/jama.2018.14854

Additional Reading
  • Bryant CX, Green DJ. ACE Personal Trainer Manual: The Ultimate Resource for Fitness Professionals. San Diego, CA: American Council on Exercise; 2010.

  • Recommendations for Physical Activity. National Institutes of Health.