All You Need To Know About Cardio For Weight Loss And Building Muscle

Cardio.

One of the most controversial topics in the fitness industry.

You hear everything ranging from:

“You don’t need cardio to lose fat!”

“Cardio is only going to kill your gainz bro!”

All the way to:

“If you want to lose fat, you should be doing a lot of cardio because it burns the most calories and the more calories you burn, the more weight you lose!”

“You should be doing cardio every single day!”

And I understand.

It can be quite frustrating for someone like you to know exactly what to do with so much contradicting information out there on the internet.

However, luckily for you, with my no-bullshit, no-nonsense, transparent, and efficient approach to fitness, I’m going to tell you all you need to know about cardio for weight loss and building muscle.

Here’s what you can expect from this article:

• What Is Considered Cardio
• Why Do Cardio
• How Much Cardio You Should Be Doing
• Types Of Cardio
• The Best Forms Of Cardio
• Combining Cardio And Lifting Weights
• Common Cardio Myths

(I have also covered cardio in one of my podcasts. Click here for the video version and here for just the audio version.)

What Is Considered Cardio

A lot of people tend to think that cardio simply means hopping on your most common cardio machines at the gym, usually the treadmill, elliptical, and spin bike, and then going at it for hours until you’re either drenched in sweat or completely drained of motivation.

While these types of exercises are included under the vast umbrella of cardio, cardio often includes many, many other forms of movement.

The term cardio is short for the cardiovascular system or the system of organs that function together to transport oxygen, carbon dioxide, and blood throughout your body.

Simply put, cardio is considered any type of movement or exercise that directly enhances or strengthens the cardiovascular system of which the major players are the heart, lungs, and blood vessels.

When we translate this to exercise, it’s basically any type of exercise that raises our heart rate and breathing rate for an extended period of time (usually at least 10 minutes).

As you can see, there are plenty of exercises that meet this single requirement.

However, what might surprise you is that lifting weights does not meet this requirement (before you get confused or go wtf, keep reading).

Why Do Cardio

A common question I get is, “why do I even need to do cardio? Isn’t it only for fat loss?”

And here’s my answer:

You should be doing cardio because, as stated above, it strengthens your cardiovascular system which is arguably the most important organ system in the body because it works day after day to keep your body running and alive.

The stronger this system is, the more efficiently it runs. The more efficiently it runs, the longer your body’s hardware will last. This means you’ll live a better and longer life. Win-win.

I would also argue that cardio is even more important than lifting weights. There, I said it.

While there are many benefits to lifting weights, if I were hypothetically forced into a situation where I had to choose between either doing only cardio or only lifting weights, I would choose cardio.

You’re probably asking, “why??”

Well, think about it this way, which system is more important for survival and longevity?

Your cardiovascular system? Of which contains your heart, lungs, blood vessels, etc.

Or your musculoskeletal system? Of which contains your bones, muscle, tendons, ligaments, etc.

(I’m hoping you said the first one)

While yes, I understand it’s cool to have big, round, voluptuous glutes or a spectacularly impressive bicep peak if your heart, lungs, and blood vessels were missing or failed to work, you wouldn’t live very long…

On the other hand, you could have the flattest glutes in the world with almost non-existent biceps, but if your cardiovascular system was in tip-top shape, you would live a long, fit, and quality life despite your lack of muscle.

So I would say it is quite important that you need to do cardio for your overall longevity and health.

To address the second part of this question, while yes, cardio can burn a ton of calories, you shouldn’t only be doing it when you’re actively trying to lose fat.

Much like muscle mass, if you don’t use your cardio fitness, you lose it.

While you’ll feel super fit during your dieting phase, you might feel like you get out of breath easier doing mundane tasks like walking up the stairs if you completely cut out cardio.

Simply put, the fat loss benefits of cardio are overrated while the actual health benefits of cardio are underrated.

Lastly, as you’ll see later on in this article, cardio doesn’t actually burn as many calories as you think.

How Cardio Can Help With Lifting

An uncommon piece of knowledge is that cardio can actually aid with lifting weights.

This is due to the aerobic adaptations you get from doing cardio.

If you aren’t familiar with what this means, allow me to explain.

When performing an exercise, we will primarily rely on either our anaerobic (meaning without oxygen) or aerobic (meaning with oxygen) system.

Think the next time you need a sudden burst of energy to jump, sprint, or lift weights, these are short periods that require a ton of energy, but not long enough for you for your breath to catch up with the demand. This is when and where the anaerobic system shines. It allows your body to get a quick burst of energy (anywhere up to 2 minutes) before being depleted.

However, as you can see, the anaerobic system also has a drawback. Its energy can’t be sustained for very long. So for longer duration events like running or biking for several miles or even something as simple as having to provide energy for you while sitting on the couch (you still need the energy to keep you alive), it’ll need an alternative energy source. This is where the aerobic system comes in. Luckily, when we’re doing something at low or moderate intensity, we’re able to keep steady breathing going to bring in lots of oxygen for the aerobic system to act.

So how does this relate to cardio and lifting weights?

While we’re lifting weights and doing our sets, the anaerobic system is hard at work repping out your set.

But as soon as you’re done?

You’re able to get a steady breathing rhythm going and activate your aerobic system.

So in order for your anaerobic system to recover, the aerobic system must be working harder.

And what are some actual ways cardio can benefit lifting?

• Less recovery time in between sets – by making your aerobic system more efficient, it allows you bring more blood to the muscles and you’ll recover and catch your breath quicker in between sets
• More nutrients to muscle – by strengthening your heart, lungs, and blood vessels, this allows your muscles to be able to receive more nutrients like oxygen while training to increase your performance
• Increased muscle growth and performance – there seems to be an ongoing joke in the fitness community being “anything over 6 reps is cardio.” While it might seem funny, it is actually quite sad because there are some benefits to muscle growth and performance from working in higher rep ranges. Incorporating some cardio will make high rep work feel much easier.

Does Cardio Build Muscle?

A question I also get a lot is: “do I need to lift weights if I do cardio? Won’t cardio be enough to build muscle?”

Yes and no.

The driver of muscle growth is progressive tension overload meaning that when your muscles experience some sort of tension they aren’t used to, it triggers them to adapt by getting bigger and stronger.

With this in mind, if you go from being completely sedentary to doing cardio, your muscles go from experiencing minimal tension of getting up every now and then to doing a consistent amount of cardio. This leads to some muscle growth as your muscles have to adapt in order to perform cardio.

However, it is very difficult to continually build muscle to a meaningful degree with cardio alone.

You are much better off using cardio for the cardiovascular benefits and using weights for the muscle and strength-building benefits.

How Much Cardio You Should Be Doing

Now, as a general recommendation for all of my clients, I recommend getting at least 150 minutes of moderate-intensity cardio per week.

Of course, I didn’t just pull this random number out of thin air.

It is also the same recommendation made by the World Health Organization (WHO), the American Heart Association (AHA), and the American College of Sports Medicine (ACSM), and the Centers for Disease Control and Prevention (CDC).

Now, obviously, as a coach who strives to meet my clients where they are at rather than forcing a one size fits all recommendation onto everyone, for anyone who is new or returning to physical activity after a long layoff, I do not recommend 150 minutes of moderate-intensity right off the bat because:

• Some people may not be ready for immediately going from 15 minutes to 150 minutes per week
• Some people may not be ready for moderate intensity right away
• Some people may not have 150 minutes to begin with
• And of course, some people may not be physically able to perform that much exercise right away

And all of this is fine.

Do I think 150 minutes could be an end goal for most people?

Absolutely.

But everyone can and should work at their own pace to get as close to that recommendation within their own circumstances.

The main thing is that you start with a duration you’re comfortable doing and can stay consistent with, and then find ways to progress from there.

Now, at this point, people usually ask, “so what is moderate intensity anyway? How do I tell?”

Types Of Cardio

If you wanted to get all nitty-gritty we could talk about heart rate zones.

However, in an effort to keep things simple, here’s a guideline that’s both effective and simple to use:

• If you can comfortably hold a conversation while performing your bout of exericse, that is considered low intensity.
• If you can hold a conversation, but need to take pauses in order to catch your breath in between sentences while exercising, that is considered moderate intensity.
• If you can’t speak whatsoever while exercising, that is considered high intensity.

The Best Forms Of Cardio

Okay, I lied (sorta).

There is no “best” form of cardio.

Really, the best form of cardio is, as you probably guessed, the one that you can stay consistent with and enjoy.

However, with that being said, people (you and me included) don’t like this open-ended answer.

We want to be told exactly what to do, how to do it, and without the guesswork.

So, if that’s what you want, then I’ll give you my list of what I think are the best forms of cardio.

Now, keep in mind this is purely based on my opinions and experiences.

If you prefer forms of cardio that aren’t on this list, then by all means go for it. Like I said earlier, enjoyment + consistency matter way more than effectiveness.

And ultimately, when we’re talking about cardio, we also need to take into consideration what your goals are.

If your goal is preparing to run a marathon, it would make no sense for you to do swimming for your cardio sessions.

If you want to get maximally jacked and muscular, it would slow down your progress if I told you to do hill sprints for your cardio sessions.

If you just want to focus on losing fat because you’re 100 lbs overweight and I told you to go jogging for cardio, it would very likely compromise the health and condition of your joints.

But generally, the things I look for when prescribing cardio are:

• Accessibility – will someone need access to fancy equipment or can they do it with minimal to no equipment?
• Impact – how much impact will performing this exercise have on their body and joints?
• Calories Burned (when someone’s main goal is fat loss) – how many calories will this exercise burn per session relative to other modes?
• Interference With Muscle Growth (when someone’s main goal is to build muscle) – how much will this exercise interfere with the process of recovery for muscle growth?

Also considering the fact that most of the people I work with are looking to build muscle, lose fat, get fitter, and want to improve their overall health and longevity, this is what my recommendations boil down to:

• Walking. If I had to pick one, it would be walking. Walking is the simplest, easiest, and most readily accessible mode of exercise. Walking is also incredily low impact so it won’t lead to any excessive joint stress and/or interference with weight training. Many people only view it as “just walking”, but walking still gets the job done of increasing your daily activity to burn calories as well as improve your cardiovascular health to the extent that most people are looking for. In fact, for most of my clients, the only fitness regimen I prescribe is a weight training program and keeping a step count which works well enough for many to change their body and improve their health.
• Elliptical. A runner up (no pun intended) to walking would be the elliptical. Again, the elliptical is simple and easy to use, its low impact nature allows to be done by most people, and the elliptical is going to burn more calories versus other modes of cardio because the more movement your entire body does, the more calories you are going to burn. Really, the only reason this is in second place is because you need an elliptical machine whereas walking doesn’t need any equipment.
• Swimming. I chose this one for similar reasons as the elliptical. It requires full body movement (great for burning loads of calories) and very low impact. However, this is third because there’s a bigger learning curve for someone to learn and get proficient at swimming than hopping on a piece of cardio equipment (and of course there’s the need for a pool, change of clothes, etc.).
• Cycling. Simple, easy to use, low impact. However, not as readily accessible and doesn’t burn a whole lot of calories because you’re mostly seated and only using your legs.

And because I know some of y’all will skim this article, let me say it again:

The best form of cardio is the one that you can stay consistent with and enjoy.

Just because I didn’t list it here doesn’t mean you can’t do it. This list is not gospel and is my opinion only.

Combining Cardio And Lifting Weights

A common question I get regarding combining cardio and weights is, “should I do cardio or weights first?” or “how much cardio sessions and weights sessions should I do?”

Here’s the answer that everyone hates but it’s the truth: it depends (on your goals).

Really, there is no one size fits all answer because it depends on many factors like:

• What is the main goal you want to achieve?
• What does your schedule look like? Are you able to fit in activity daily or can you only dedicate specific days to working out?
• How far do you want to excel in either training style?
• How much stimulus is your body able to handle and adapt from?

But here are some things to think about to best help you answer your question.

Firstly, in a perfect world if you had the schedule to work out whenever you wanted, I would say space your cardio and weights session on different days. This is so that you are able to really give your workouts your all rather than having to do two different modes of exercise in the same session and being too fatigued to do the other one.

But again, this is in a perfect world that many don’t get the opportunity to live in.

Many of us aren’t able to build our entire lives around fitness. In that case, keep reading.

Generally, when we think about what to do first in terms of exercise order, we want to start with the thing we want to prioritize.

This is because at the beginning of your workout, you’re the freshest physically and mentally and as you go through your workout, your last exercises don’t get as much love and attention as your first ones.

So if your main goals are strength and/or muscle building related (this includes wanting to lose fat and look better naked), then I recommend you start your workout with your weights session and supplement your cardio afterward.

However, if your main goals are to improve your cardiovascular health and/or prepare for a cardio-related event like a bike race, marathon, triathlon, etc., then I recommend you start your workout with your cardio session and supplement with your weights session afterward.

“But what if I don’t know which one I want to focus more on?”

In that case, start with the thing that is going to be the highest intensity or demand the most out of you.

(Not being biased, but in most cases, this is going to be lifting weights)

This ensures you are fresh to push yourself at high intensity. And as you would normally get fatigued throughout the workout, the next less demanding exercises will require less of you.

And as a reminder, as mentioned above, cardio doesn’t interfere with lifting to build strength and/or muscle as long as you do both of them in moderate amounts.

In moderate amounts, cardio and weight lifting can actually work together and have mutual benefits.

Common Cardio Myths

If there aren’t stupid, outrageous, and completely made-up claims about something, is it really even part of the fitness industry?

With that being said, I have compiled a list of the most common myths I have heard about cardio.

“Cardio will kill your gainz bro”

Commonly preached by your average gym bro, but with zero context to support it.

Walking or doing some sort of light to moderate intensity cardio is not going to magically melt all of your muscle off.

Otherwise, the human race wouldn’t have survived and our ancestors would have died off a long time.

Cardio won’t kill your gainz unless…you do too much of it too frequently, you’re not eating enough calories, or you’re not managing your recovery from training properly.

So stop fearing and avoiding cardio and do it. It’s good for you and your heart and your 70-year-old self will thank you.

“Cardio will burn less calories over time because you get efficient at it”

This one comes from ignorance and misunderstanding more than anything.

Here’s the thing.

Will your body get more efficient at cardio as you get better and fitter?

Absolutely. Like any other skill, your body likes getting efficient and saving energy. It’s inherently lazy.

So technically, yes you will burn fewer calories when you’re comparing when you first ran a mile versus you running a mile 6 months later.

However, are you going to be running that same mile at the same exact speed 6 months later?

Probably not. You’re likely going to feel fitter and in better shape which means you’ll be able to run faster and longer.

And because your perceived exertion goes down, you’ll be able to push yourself harder and do more, which ultimately leads to more calories burned, not less.

“You should do cardio fasted/on an empty stomach because it burns more fat”

This one has a bit of truth in it.

While yes, you will burn a bit more fat working out fasted, in the end, it doesn’t make a difference at all.

Because a common misconception is the fat burning is the same as losing body fat, but these are two different things.

Burning fat is simply fat oxidation or converting fat into energy whereas losing body fat is the process of actually losing fat mass.

Technically, you could burn fat all day every day if the only thing you ate was dietary fat.

However, you wouldn’t lose any body fat at all unless you were in a calorie deficit.

Which all comes back to a calorie deficit being the main driver of fat loss.

Think about your body as a car, whether you drive your car 20 miles during the day or 20 miles during the night, it’s still going to use the same amount of fuel.

With all this in mind, whether you do cardio fasted or fed if your calorie deficit remains the same, then you’re going to lose fat at the same rate.

“HIIT is better for fat loss”

This myth has been perpetuated for as long as I can remember.

The reasoning behind it is always something along the lines of “HIIT has the ‘afterburn’ or ‘EPOC’ effect so it burns a ton of calories throughout the day!”

When in reality, it doesn’t…

Here’s the truth about the afterburn/EPOC effect: the data has shown that the effect only accounts for an extra 6-15% of the total calories burned during the session.

This means that for your average 15 minute HIIT cardio session that burns 100-150 calories?

You’re only burning an extra 6 to 22 calories from the afterburn effect…

“But what if I do a longer HIIT session?”

If you’re doing a true, all-out HIIT session (hence the part of the name “high intensity”), you won’t be able to do that for more than 15-20 minutes.

Even professional athletes don’t do HIIT cardio for that long or that frequently because of how demanding it is. (I’m not trying to roast you here, I’m just stating the facts)

Furthermore, a lesser-known fact is that the afterburn/EPOC effect happens with low to moderate intensity exercises, too.

And with low to moderate intensity levels of exercise, you’re likely able to go harder and longer (that’s what she said).

This means you’ll burn more calories during the session and from the afterburn/EPOC effect while exercising at low to moderate intensities.

And not to mention that HIIT is very physically taxing and can be harder on your joints.

So really, there’s absolutely no need to do HIIT cardio unless you’re an athlete training for a specific sport that requires it.

Because really, the purpose of HIIT is for high-level athletic performance. Not for your everyday guy or gal looking to get in shape.

“Cardio is all you need to lose weight”

I honestly think this myth is starting to become less and less prevalent.

This is hugely in part to many reputable fitness icons, coaches, etc. (like myself – shameless plug) who are promoting lifting weights for weight loss.

However, I still see people who check into the gym and spend day in and day out doing hours of cardio hoping to lose weight.

The reasoning usually goes along the lines of “you need to burn calories to lose fat and you can burn more calories doing cardio than other forms of exercise.”

While yes, this is true, but it also won’t likely yield the results that you want.

First and foremost, you need to be in a calorie deficit to lose weight.

While yes, you can get into a calorie deficit through only doing cardio, for most people, it’s likely because they are overeating calories.

In terms of efficiency, it’s much less work to put the fork down and stop 500 extra calories than it is hopping onto the treadmill and try to burn 500 extra calories.

Secondly, doing lots of cardio has been shown to increase hunger levels significantly which obviously doesn’t help when you’re trying to stick to a deficit.

Thirdly, even if you are doing all those things above correctly, cardio might not lead to the physique that you want.

I’m not shaming anyone who wants or has this body type, but many people say that cardio has only led them to “have the same look but smaller” and/or “look skinny-fat.”

Contrary to another popular belief, cardio is not the best way to get “toned” and “defined.”

“Cardio is best way to tone”

I fucking hate the word “toned.” But for the sake of this article and using a term people are familiar with, I’m going to use it.

But the previous sentence actually segways nicely into our next point.

Cardio is not the best way to tone or get muscle size/definition for this reason.

Getting “toned” or “muscle size/definition” requires two things:

1. Building muscle mass
2. And losing overall body fat to reveal said muscle mass

So while simply just being in a calorie deficit will lead to fat loss, it won’t fulfill the other crucial part of getting “toned” which is building muscle mass.

If we want to build muscle mass effectively and efficiently, we must implement some sort of strength training program.

Lastly, the harsh truth is that you can’t diet your way into a good physique.

“Make sure you’re doing cardio in the fat burning zone”

If we really want to talk about outdated information, here it is.

I spent most of my novice fitness years believing that I would die with this chart by my bedside.

However, I am so glad I changed my position on this shortly thereafter.

Because it’s largely a myth and pseudoscience at best.

It is mainly loosely based on this information where if you’re working at higher intensities you will use more carbs as energy whereas if you’re working at lower intensities you will use more fat as energy.

Although this is true, based on the enormous amount of research today, time and time again it seems that fat loss all boils down to whether you’re in a calorie deficit or not and the size of that deficit (look, there it is again…) regardless of where those calories come from.

So if you want to burn fat, focus on your calorie deficit with nutrition being your focus and cardio being a supplement to that.

Whether your heart rate is above or below these zones, it doesn’t matter for fat loss. As long as you’re in a calorie deficit, you will be losing fat.

However, if you do want to pay attention to heart rate because you want to train for a specific fitness goal or because you need to monitor your blood pressure, these are certainly valid reasons to do so.

Final Thoughts

And lastly, to wrap up with a quick recap of this article as well as my final thoughts on cardio.

• Cardio is considered any type of exercise that elevates the heart rate for an extended period of time that is at least 10 minutes long.
• Cardio is so important and underrated for overall health and wellness. It is not just a tool for fat loss and burning calories.
• Although too much cardio can impact lifting performance, doing some cardio will actually aid lifting performance.
• As a general rule, 150 minutes of moderate intensity is recommended for anything looking to get the benefits of improved cardiovascular health.
• A simple way to differentiate between cardio intensities:
  • Low – able to hold a conversation while performing exercise
  • Moderate – able to hold conversation but taking breaths in between sentences
  • High – not able to hold conversation at all
• There is no “best” form of cardio, but here are my top recommendations (chosen because of accessibility, impact and stress on body, calories burned, and interference with muscle growth):
  • Walking
  • Elliptical
  • Swimming
  • Biking
• If you are looking to combine a cardio and lifting program, you should do the thing that you want to prioritize first. This way you are fresh at the beginning of the workout and can push harder whereas you’ll be more fatigued for the other mode of exercise. If your main goal is building muscle, building strength, and/or improving body composition then lift weights first. If your main goal is to improve cardiovascular health and performance, then do your cardio first. If you don’t have a preference, do the one that will be more demanding first.

And if you want my thoughts on common cardio myths, just simply scroll up 🙂

Yes, I understand there is a lot of stupid, misinforming fitness information out there, but hopefully, this article at least clears some of it up for you.

As always, reach out if you have any questions or concerns with anything at all.

Until next time

-Aus

Coaching Opportunity

I am currently taking on new clients for online coaching.

A few benefits of this program include:

• Customized nutrition plan tailored to your individual needs and goals
• Customized training plan to help you build muscle, lose fat, and feel better
• Daily accountability and support to ensure that you never feel “alone” or “stuck” on your journey to bettering yourself.

The best part: you can do this from anywhere in the world.

You can apply here for more info.