QUESTION: I wanted to know how much cardio you recommend doing a day to lose weight?
Like how many minutes a day? How many days per week? What intensity? What kind of cardio exercise? And how much would you consider to be “too much?”
ANSWER: If you’re a regular reader of mine, then you probably know my general opinion of cardio for the specific purpose of burning calories and losing weight.
Which is… I think it’s highly overrated, inefficient, and mostly just sucks.
Let me explain why.
5 Problems With Doing Cardio To Lose Weight
If you’re planning on doing cardio to burn calories and make weight loss happen, there are a few important things you need to know.
1. It Burns Fewer Calories Than You Think
Yes, cardio burns calories which means it can help you lose weight. Awesome.
However, it burns surprisingly little compared to what most people incorrectly assume (source), and much less than what most trackers, apps, wearable devices, and cardio equipment will claim.
For example, a variety of studies (sources here, here, here, here, and here) show various smart wearable devices (e.g. FitBit) aren’t accurate when it comes to tracking calories burned. Most are good enough for tracking steps and heart rate, but they overestimate how much you’re burning.
The truth is, most people doing typical forms of cardio at a typical intensity will end up burning about 5-10 calories per minute. Possibly a little more with a higher intensity activity and/or if the person weighs more than average (a bigger body burns more calories than a smaller body).
But, generally speaking, most people are only going to burn 5-10 calories per minute.
So… 30 minutes on a treadmill? You’ll probably burn 150-300 calories.
An hour on the bike? Maybe 300-600 calories.
Sure, this is still certainly something, but it’s really not that much… especially given the amount of time and effort it takes. And yes, even the “afterburn effect” (aka EPOC) causes significantly less calorie-burn than most people think (source).
This means that cardio has much less of an impact on losing weight than most people realize.
2. It’s Inefficient
Now that you know how many calories cardio actually burns, you can see that you’d need to do a lot of it (often) and/or very high intensity forms of it (often) for it to truly have the significant calorie-burning, weight-loss-causing effect most people would like it to.
The problem with this – besides the fact that excessive amounts of cardio can cause problems of its own (more about that in a minute) – is that it makes cardio an inefficient method for creating your deficit.
Think about it.
To create a daily 500-calorie deficit, you could either A) go to the gym and spend 60 minutes on a treadmill every single day (or however many days per week you plan to use exercise to create your deficit), or B) simply not eat those 500 calories in the first place… a task that literally takes zero seconds to accomplish and can be done anywhere, anytime.
See my point?
Not to mention, it’s ridiculously easy to out-eat whatever amount you’re able to burn. We’re talking wiping out an hour of cardio with just a couple of minutes of eating/drinking more than you intended.
And sure, something like HIIT will burn more calories in less time than a lower intensity activity, but A) it can’t be done for as long, so the total calories burned will often be similar in the end, B) it’s much harder and requires a lot more physical and mental effort, and C) it’s still way less efficient than just eating a little less.
3. It Can Lead To Overeating
Here’s a scenario that happens all the time with people who are trying to lose weight.
A person will do some cardio and assume they burned a lot of calories. In reality, they actually burned much less than they think they did.
But they don’t know this.
So what will often happen at some point later is the person will think “I jogged on a treadmill for 30 minutes today, surely I can now afford to eat this additional 1000-calorie meal.”
And they do that, never realizing they actually only burned 200-300 calories. Which means they unknowingly cancel out whatever deficit they may have created via cardio, and possibly put themselves into a surplus in the process.
This concept of “eating back the calories burned” is one of the many reasons you hear people saying stuff like “I’ve been working out all the time but I’m still not losing weight!” or “I exercise a ton but I’m somehow gaining weight!”
In addition to this, some people find that doing cardio makes them waaaay hungrier than they’d otherwise be, and that alone can lead to overeating.
4. Too Much Of It Creates New Problems
Too much of any form of exercise will cause problems, and in my experience, cardio tends to be the type of exercise people overdo the most… probably as a result of trying to burn a useful amount of calories, or lose weight faster, or make up for a poor diet (yeah, good luck with that).
Now what kind of problems are we talking about here?
- Overuse injuries, which cardio is a common cause of due to the repetitive movement and impact stress on the knees/ankles.
- Recovery related issues, not just in terms of the body parts being used the most (typically the legs with most forms of cardio), but also the central nervous system (CNS)… which affects everything.
- Muscle loss and strength loss, because when recovery is an issue, the risk of losing muscle and strength increases quite a bit.
- Worsening many of the hormonal and metabolic issues that occur while in a prolonged deficit (e.g. increased cortisol levels, metabolic slowdown, water retention, etc.). Basically all of the things that make losing weight hard. Doing excessive amounts of cardio makes it all even harder.
5. It’s Not Needed
This is more of a fact than a problem, but it’s an important fact.
And that is, for the purpose of losing weight, cardio isn’t needed at all.
The only thing that’s truly required to lose weight is a caloric deficit, and that can very easily be accomplished entirely through diet alone, making cardio completely optional for the purpose of losing weight.
How Much Cardio Should You Do To Lose Weight?
With all of that in mind, let’s get back to that original question.
How much cardio should you do a day to lose weight?
Well, since we know that losing weight is all about being in a sustainable caloric deficit, and we know this can be accomplished entirely through diet alone, the amount of cardio that should be done for this purpose falls somewhere between “none” and “some.”
And the best way to help you figure out where you land on this spectrum, and exactly what “some” would entail for you, is to simplify my recommendation down to this…
For losing weight, everyone should do the the least amount of cardio necessary.
What does this mean exactly?
Well, if you’re someone who is able to create a sustainable caloric deficit through diet alone and you don’t need or want to do any cardio for that purpose… guess what?
You can feel free to do zero cardio for that purpose.
That’s how I approach fat loss myself, and it’s what I recommend to most people who want to lose weight. At least, for a while.
On the other hand, if you find that you need or simply prefer to do cardio to help you create a sustainable caloric deficit – and it’s done in conjunction with your diet doing most of that work – then you should absolutely feel free to do cardio for that purpose.
How much should you do exactly?
The least amount necessary.
That means using your diet as the primary method for creating your deficit, and then using cardio as a secondary tool for helping you make that deficit exist on any given day in accordance with your needs and preferences on that day.
Whatever that amount of cardio is for you, do that much.
Here’s An Example
Let’s pretend some example person figured out their maintenance level, created an ideal-sized deficit, and came to the conclusion that they need to be at about 2000 calories per day for fat loss to occur.
To make this happen, our example person can:
- Consume 2000 calories per day and do no cardio whatsoever.
- Consume more than 2000 calories per day and do an amount of cardio that makes up the difference. (So if they ate 2500, they’d do enough cardio to burn 500 calories.)
With all else being equal, both of these options will have the exact same weight loss effect for this example person. As long as the same deficit is present in the end, the same rate of weight loss will occur.
Your goal is to figure out which option is most preferable, efficient, convenient, and sustainable for you… and do that.
If that happens to be the first option (my personal preference and what I recommend most), that’s fine. How much cardio should you do to lose weight? None.
If it happens to be the second option, that’s fine too. How much cardio should you do to lose weight? The least amount necessary to make it work for you.
Now let’s answer some follow-up questions you probably have…
What type of cardio activity is best for losing weight? Treadmill, bike, elliptical, swimming, sports, classes, etc.?
With all else being equal (frequency, duration, intensity), it’s not going to matter. The difference in calorie-burn between different activities is minor at best.
So, choose whatever activity is most PECS (preferable, enjoyable, convenient, sustainable) for you and makes you most likely to be consistent (aka The PECS Method).
Additional details here: What Are The Best Fat Burning Exercises?
What intensity should my cardio activity be for losing fat? Low, moderate, or high?
For the vast majority of people, low or moderate intensity will be perfect.
I know high intensity cardio sounds the coolest, seems the most special, and will certainly make you feel the most tired and sweaty afterwards (which is fantastic if you’re interested in things that don’t matter).
But the reality is, high intensity cardio for fat loss purposes serves as a lovely way of increasing the potential for problems with little benefit to show for it.
That’s not to say it can’t or shouldn’t be done. It’s just to say that you don’t need it, and it’s both less useful and more problematic than most people realize.
I recommend sticking with low/moderate intensity cardio instead.
When is the most effective time of the day to do cardio?
With all else being equal (frequency, duration, intensity), it will be equally “effective” (i.e. burn the same amount of calories) regardless of when you do it.
Feel free to do it whatever time is most PECS for you.
Should I do cardio or weights first if I’m doing them back-to-back?
Weights first, cardio second.
Of the two, weight training is the activity that typically warrants being in your freshest, strongest, and least fatigued state. So, it makes sense to do that first.
Additional details here: Should You Do Cardio Before Or After Weights?
Do you ever recommend more cardio for certain people?
More cardio than the “least amount necessary”?
For weight loss, that recommendation applies perfectly to everyone.
However, there are certain scenarios when cardio can become a more necessary fat loss tool.
The main scenario that comes to mind is someone who has lower calorie needs.
One example of this would be someone who is trying to go from lean to very lean. Or someone who is smaller (i.e. short, lower body weight) and/or sedentary (see: The 1200 Calorie Diet).
In cases like these, it might make sense to start burning more rather than eating less, because eating less when calorie needs are already low is going to be problematic.
Not just for sustainability, but for health and avoiding nutrient deficiencies. (Additional details here: Very Low Calorie Diets)
But note that even then, cardio is still secondary to diet, and the recommendation is still to do the least amount necessary. It’s just that the necessity is greater in a scenario like this.
How much cardio is too much?
Think of it like this.
Are you losing weight at a healthy and sustainable rate, without experiencing any of the potential downsides of cardio that we talked about earlier?
If so, it sounds like you’re doing an ideal amount of cardio.
If not, it sounds like your balance between diet and cardio is off, and you need to focus more on your diet and less on cardio for the purpose of making your deficit exist.
How much cardio do you recommend for overall health?
I answer it in detail here: How Many Steps Per Day And How Much Cardio Per Week For Health