May 20, 2017 Damon Hayhow

Why You Should NOT Do Cardio


“Cardio” is, by definition, exercise to remedy heart disease. Despite baffling widespread misconceptions, the term “cardiovascular exercise” does not mean, imply or suggest the improvement of body composition in athletes; nor does it mean the ability to perform well in endurance or aerobic activities. Adding ‘cardio’ to the training regime of any athlete (or serious trainer) is one of the worst mistakes anybody could make.

Cardio is called ‘cardio’ because it is a medical intervention for people with (or at risk of) cardiovascular disease. Look it up in the dictionary. The word ‘cardiovascular’ means: “relating to the heart and blood vessels”.

In application, cardio is literally meant to achieve a level of physical mediocrity from which a person could start doing more serious sports training without dying of a heart attack. This isn’t opinion but documented fact (more on this later). “Cardio” was never meant to improve athletes or achieve athlete-levels of bodyfat or muscularity. It is basically the lowest form of exercise sick people can do before they can start training for sport.

Cardio, Health and Bodybuilding

Achieving a BMI under 25 is a primary pillar of Global clinical health objectives, and bodybuilding goals directly contradict it. The importance and priority of this clinical marker is emphasised throughout documents by the WHO (World Health Organisation) to every western nation’s health department, including the Australian Health Department. Rightly or wrongly, low BMI is a foundation measure of health. And ‘cardio’ is the name given to exercise prescribed to achieve it!

From a clinical standpoint, bodybuilding is a direct cardiovascular risk because it aims to increase BMI; usually above 25. All of the acknowledged failings of BMI as a clinical tool do not matter to the bureaucrats, lawyers and doctors. There are actually numerous clinical health markers that bodybuilding practices contradict (beyond the scope of this article). And this is why health professionals are often so harshly critical of bodybuilding, claiming bodybuilders are at massive risk of heart, kidney and liver failure. There is absolutely no evidence of bodybuilders matching the rates of heart, liver or kidney disease of the general public, let alone suffering disproportionately more. But from the health and medical community’s point of view, bodybuilding directly contradicts the mediocrity that they want for the public. So if you want to bodybuild, do not ask health professionals for their advice or recommendations. They absolutely want you to fail, so that you meet their documented goals.

What Cardio is & Who Its For

‘Cardio’ is generally accepted to mean sustained, low intensity aerobic exercise specifically because that is the lowest risk activity suitable for sedentary obese people with cardiovascular disease. With around 1/2 of western populations horribly overweight and completely inactive, telling them to just go for a walk to not die is an understandable and laudable recommendation. But for the exact reason that ‘cardio’ is relevant to these people, it is thoroughly irrelevant to people already training like athletes for optimal body composition.

Athletes are, by definition, not sedentary and typically meet the clinical recommendations for activity that constitutes ‘cardio’. Exercising for a half hour, 3x weekly means ‘cardio’ has already been done by athletes.

Even though the training done by athletes greatly affects the cardiovascular system, sports training is not ‘cardio’ because the purpose is not to improve clinical cardiovascular measures; it is to improve sports performance, potentially in direct contradiction to clinical markers of cardiovascular “health” (ie reduce BMI, lower cholesterol, decrease systolic BP etc). This is not an argument of semantics because claiming that sports training is ‘cardio’ infers that any form of cardiovascular exercise is equally valid for achieving the same sports performance outcome. Everybody knows that walking will not help an olympic swimmer swim faster or longer; they need to practice swimming. This is the danger of using wrong language to describe an activity.

Even though sports training achieves the same ends of being engaged in physical activity when ticking the boxes on the health check form, all sports training by athletes is vastly superior to ‘cardio’ for improving body composition, as proven by the standards of body fat in athletes being dramatically lower than ‘fitness’ sought by ‘cardio’ (see here…). Specifically, fitness (the goal of cardio) in men is quoted as being 14-17% fat where an athlete is 6-13%; for women athletes are 14-20% while ‘fitness’ means being a fatter 21-24%. To a bodybuilder, ‘fitness’ levels of bodyfat is horrifyingly fat.

But still, the overriding, crucial, documented, fundamental clinical objective of ‘cardiovascular exercise’ relevant to bodybuilders is a Body Mass Index (BMI) below 25; in other words, a bodyweight of 72kg or less in an average 170cm person (man or woman). (Discover just how skinny-fat cardio is intended to make you here…)

Cardio is literally an activity that is documented and designed to be simultaneously irrelevant and completely opposing the objectives of bodybuilding. It is literally only intended for large, fat, sedentary non-athletes; which bodybuilders are not. And it is designed to create small, fat, average, non-athletes, which bodybuilders do not want to be! ‘Cardio’ is a remedy to sickness, as all health initiatives are; not an activity with any relevance to athletes; especially not bodybuilders.

The fact that most people believe cardio is relevant to bodybuilders does not make it true. The fact that many successful bodybuilders have engaged in huge volumes of cardio and yet failed to reduce their BMI below 25, or raise their bodyfat above 14%, actually means their ‘cardio’ failed dismally! The fact that they looked good was not due to their intelligent use of cardio. It was absolute dumb luck that the cardio failed to do what it is documented to be designed to do!

What about Burning Fat?

But what about burning fat? Firstly, this argument ignores everything about the documented purpose of cardio. Putting it back into context, cardio is assumed to reduce bodyfat percentage with BMI because it is intended for sedentary obese people who are likely to have disproportionately more fat to lose than muscle. It would be ludicrous to expect the same outcome in athletes whose body’s already struggle to maintain their inflated muscle mass; especially when those athletes want to drop below 6% bodyfat; especially when the published figures (linked above) show the bodyfat level of ‘fitness’ to be above 14%!

But in answer to the question, burning fat is as irrelevant to getting leaner as an hourly wage is to becoming wealthy. You do not become extraordinarily wealthy by working more hours at McDonalds. Similarly you don’t become extraordinarily lean by thinking you can trick the body into burning off its fat reserves by training to be a crappy, weak, bad athlete. The body is an adaptive organism; not a machine.

When it comes to fat, all you want to know is whether you are getting leaner over time as a result of your intervention (diet and training). You do not need to know when the fat is being burned just as you don’t need to know when your hair or muscles are growing, your skin is repairing or the cells of your eyeballs are renewing. The body does what it needs to, when it needs to.

Intelligent body recomposition is very simple and involves worrying about those things you can see and measure. That is, your weight, you bodyfat, your food intake, and your strength. Those 4 variables are the only variables relevant to achieving any body composition outcome. So:

  • measure your body composition (ie weight, fat mass and lean mass)
  • set a goal body composition which should involve maintaining or gaining muscle (lean mass)
  • prescribe a diet you think will step toward your bodyweight goal
  • prescribe a weight training program to get as strong as possible
  • follow your plan strictly for a week or 2
  • remeasure your body composition to assess how your diet and training worked.
  • adjust accordingly

Where does ‘cardio’ fit the body recomposition equation?

Ironically, people who argue for cardio for ‘burning fat’ generally ignore all of these relevant variables that they can so easily measure, to focus on a presumed ‘fat burning’ process that they cannot measure. They needlessly operate in total ignorance of everything that matters, to worry about things they can’t know and don’t matter. If they did measure and plan the relevant variables above, they wouldn’t prescribe ‘cardio’ because they would immediately realise that it is irrelevant at best, and negative at worst.

Cardio from Other Perspectives

When looking at cardio through the eyes of a sports coach, ‘cardio’ appears to be literally training to be the worlds worst endurance athlete. By definition, it makes absolutely no sense for any athlete to spend large amounts of time training for a physical capability that directly contradicts their sports performance goals. Endurance training is not ‘cardio’ because the purpose is not improving clinical cardiovascular markers. If cardio and endurance were one and the same then walking on a treadmill would be as valid for improving performance in a 1500m swimmer as swimming; and it’s not.

When looking at ‘cardio’ through the eyes of a Recomp coach, cardio cannot possibly help cause a positive adaptation toward an increased percentage of lean (muscle) mass. This is relevant because if you want, for example, to go from 15% fat to 10% fat then you need to go from 85% lean-mass UP to 90% lean mass (ie lean mass = muscle plus permanent stuff like skeleton and organs). This is a mathematical fact. How is walking on a treadmill going to make your body adapt by going from 85% to 90% muscle and lean mass? How can it compete with lifting weights? It doesn’t and it can’t and it was never designed to.


When you put it all together, cardio is:

  • not ever intended for athletes or bodybuilders
  • only ever designed to help make skinny-fat people from large, obese people
  • meant only to reduce risk of death from heart disease
  • documented to achieve higher bodyfat than athletes have anyway
  • irrelevant or negative to specific sports performance
  • documented to be anti-bodybuilding (primary goal of sub-25 BMI)
  • mathematically irrelevant to body recomposition

So it is as monolithically stupid for any serious trainer to practice cardio as it would be for them to use chemotherapy to lose weight. Both chemo and cardio are medical interventions intended for people with specific illnesses that bodybuilders (hopefully) do not have. Both chemo and cardio are documented as being supposed to result in body composition changes that no bodybuilder would ever want (175cm male = 70kg with 14% fat???? That ain’t bodybuilding). It makes absolutely no sense to abuse a medical intervention that is documented to achieve the opposite of what you want, in the hope it ‘works’ for your purposes by failing to do what it is supposed to.

So I strongly recommend – nay, plead – that no serious weight trainer does ‘cardio’. Ever! And I don’t mean you can get away with not doing it. I mean it is bad! It is documented to be bad. The people who invented it stated that its not meant for you, if you train, and its designed to achieve something worse than you probably are; not better! It works in the opposite direction to which you want to take your body. And it ruins the simple, elegant and intelligent body recomposition equation. There is absolutely no intelligent argument for any athlete or bodybuilder doing ‘cardio’. Don’t do it!



Giant Ranty Postscript

What about the weak, subjective, fallacious primary argument in favour of cardio: “all the champions do it”. OK. Lets just think through this, starting at the bottom of the list of who does it and then moving up to the champion bodybuilders.

Going to the local park or beach and we see PT’s everywhere training exercising their clients. We also see more people than ever walking in their lycra outfits etc. How many look incredible? Virtually none. These regular people doing regular ‘cardio’ exercise will never look like athletes because ‘cardio’ and ‘fitness’ aren’t designed to make them look like (or be) athletes. That’s fine and understandable. But why would anyone think that exercise which doesn’t make non-bodybuilders look good will somehow make bodybuilders look even better? Clearly the significant difference between the bodybuilder and regular person is not the amount of ‘cardio’ but the weights they do (and diet and supplements).

Going to a range of bodybuilding competitions this year (2017) and the overwhelming impression is that the contests shows are getting much larger, and the standards are getting much lower. Other than the biggest of shows (eg the Arnold Classic), the majority of shows are mostly populated by people lacking the muscle mass and really lacking the low bodyfat appropriate for bodybuilding competition. I absolutely agree that the vast majority of competitors are doing countless hundreds of hours of ‘cardio’ for their “comp”. This doesn’t prove you should do cardio. It proves just how worthless it is!

Of the 500+ girls who will compete in the ICN All Womens Classic (for example), probably 450 will not nearly be in condition. Its not just that they won’t have abdominal definition; the vast majority will still have visibly wobbly fat after several months of starvation and abusive quantities of ‘cardio’. Of the ones who look good, the defining quality will be they have more muscle; muscle that did not result from ‘cardio’ but from weights. Most amateur bodybuilding shows these days are a showcase of how utterly ineffective and misguided doing ‘cardio’ is. These people clearly do not need more cardio; they need to lift much bigger weights! It boggles my mind just how much failure people see all around them, over and over, year after year, and still fail to acknowledge that ‘cardio’ is failing most people as a device to get ripped for contest. Those competitors who come back improved make improvements in the weights room; not in more hours spent on the treadmill.

Scarily, filtering all the way down to the lower amateur level is staggering levels of performance enhancing drug abuse, plus narcotics. It is not uncommon to hear of young girls using steroids, clenbuterol, HGH and even smoking ICE daily, all with hundreds of hours of ‘cardio’, all to get ready for a bikini competition! Bikini FFS!?!?! That is, in order to stand onstage looking like a non-bodybuilder girl with boobs, they need to combine their ‘cardio’ with ICE plus Clenbuterol plus male hormones plus diuretics plus starvation??? Can nobody else see how absolutely insane this is? How disgustingly ineffective can a persons training be that a cocktail of drugs like that is needed just to look like a normal girl who barely trains? If ‘cardio’ is so effective, why in hell are the worlds most potent drugs needed to make a girl just look like a toned girl? Again, how much failure does your method need before you acknowledge it’s a failure?

I’ve been around top australian amateur bodybuilding for over 2 decades. And in that time I have seen countless truly gifted bodybuilder reduced to mediocrity, year after year, by cardio and low calorie diets; which is what cardio and low calorie diets are designed to do. The majority of top Aussie bodybuilders I’ve watched have competed at or around the same weight class, year after year after year. Nobody seems to appreciate just how badly someone’s training methods must be to dedicate their life to taking steroids, eating food and lifting weights and yet not grow any muscle for years. A total idiot savant should grow muscle when taking steroids, eating food and lifting weights. But training methods are so misdirected away from heavy weights, and toward cardio, that this epic failure is commonplace. That’s no surprise when you read the documented objective of those training methods: health and fitness mediocrity. Unfortunately, most bodybuilders swear that increasing their weights as they grow bigger muscles has no relationship or purpose; but going for walks at 4 o’clock in the morning when they are ready to pass out with fatigue is the best way to look like a cartoon superhero of unstoppable strength?

Back when I competed, everyone hurled abuse at me that I was wrong, wrong, wrong. They laughed at me that I’d be fat by not doing cardio. They told me I’d be injured lifting heavy into comp. So I walked onstage, literally the week after setting new Australian records in Powerlifting competitions and I won, with no ‘cardio’. I did it 3 times in 2 years, increasing my stage weight 16kg to win as an open heavyweight at 21yo. Each time I said “You see? Cardio is dumb. You don’t need to do it”. They all said the same thing “you are just a freak”. So, why does everybody say “you have to do cardio”? Its because every time someone doesn’t do it and gets a better result, they dismiss the person as a freak. And I’ve known several guys who knew nothing about comp prep, walked into comp without cardio, and destroyed everyone. Then everybody told them “you did it wrong”. So they started doing cardio and never looked as good again. But you never hear the other side of that story.

Moving up to the top pro bodybuilders we see amazingly genetically gifted athletes. These are guys and girls who typically looked more like bodybuilders before they started training, than other people do after several years of training. These are guys who typically get in shape relatively easily, some without dieting or training hard. We see the current Mr Olympia, Phil Heath, defying every sound training theory known. In training videos he uses only light weights, with sloppy form, with short ranges of motion with no focus or held contractions. He mostly standing around regurgitating cliches about hard work that everybody can see he isn’t practicing. Very obviously his unbelievable physique is not the result of superior training knowledge or competence because literally nobody else could train like Phil to look like Phil. Why is it that hard weight training is accepted as being completely unnecessary for Phil to look like a bodybuilder, but going for a walk in the morning is considered some incredibly profound ‘secret sauce’ that is essential to Phil winning? Does anybody seriously think he can half-ass his every weights workout to look like he does, but he couldnt possibly miss the daily walk or he’d look completely different? With all the steroids, thermogenics, thyroid, HGH, narcotics and god-knows what else, how can anybody seriously argue that the deciding factor on the day of the Olympia is based on who went for the most walks? Other pro bodybuilders have been known to be hopelessly addicted to narcotics, hardly train at all, go out partying for multiple days and nights at a time without sleep, living on 1 meal per day of fast-food garbage, all the way up to their competition where they still look amazing. You seriously believe that peddling a stationary bike mattered? And bodybuilders will claim that the reason they didnt look their best was because they needed more walking on the treadmill! I cannot fathom what is wrong with people’s brains? How absurdly illogical can you be? And all this hyperbolic expectation for ‘cardio’ is based on doctors said that going for walks is good to help obese, sedentary people not die of heart disease?  What the….???

So, again, looking at the people doing cardio we see that, at best, it is totally irrelevant and, at worst, the majority of people are outright failing as a result of it. ‘Cardio’ is literally designed to contradict and counteract your positive weight training, forcing ludicrous reductions in food intake, which compounds the negative effects leading to an exponentially worse physique than if you focused on lifting heavy weights for maximum performance. The fact that top pro bodybuilders can literally not train, eat crap, party on hardcore narcotics 24/7 and still have among the best physiques on the planet is not due to the efficacy of ‘cardio’, nor to their talent. Unless you are one of them you can’t do anything they do to look like they do, just like I can’t do what Shaq does to wind up as tall as him.

For anybody serious about their physique and training, not doing ‘cardio’ is the greatest competitive advantage available. By not doing cardio you remove one of the most overtly negative, self-imposed impediments to training progress that everybody else is engaged in. The fact that “everybody does it” is not a reason to follow like a lemming and do it too. It is your competition’s greatest weakness and should be exploited to the fullest! Just like all the ridiculous peak-week shenanigans that make 99% of bodybuilding competitors look much worse, avoiding their tragic, fool mistakes is the smartest, easiest way to beat them.


Damon Hayhow

Damon Hayhow has been in the body recomposition (Recomp) and bodybuilding industry for 30 years as a coach, competitor, gym owner, teacher, sponsor, show promoter, judge and MC. He has won National competitions in both powerlifting and bodybuilding, set world records, and coached others to the same success in strength sport and physique competition.

Body recomposition diet and training concepts based on logic and reason; not scientism