How to become a fat burning machine, lessons from athletes
Why become a fat burner?
In a previous post, Why some people stay skinny and others get fat I talked about how high carb foods lead to high insulin levels which effectively turn down, or off, your ability to burn fat. There is a longer downward spiral from years of this. But that was that post.
In this post, I want to look at exactly what you can do to turn yourself into a fat burning machine. This is not only about turning the fat burning on and creating a situation where you can drive a homeostasis for a steady and healthy weight, but is also about well-being and energy. My experience, as well as the overwhelming blogashpere and research itself, shows that an important benefit of fat adaptation is a much more stable energy level and well-being/mood.
We’ll look specifically at endurance athletes first. They want the same things that those who have problems with metabolic dysfunction want. They want to burn fat, not carbs, because humans have such a limited supply of carbs but much much bigger supplies of fat to draw upon. When athletes going long distances run out of carbs they are said “to hit the wall” or “bonk” (French for the noise your head makes when it hits the road?) So we’ll look at some of our lab results with an athlete later.
It’s not about treating carbs as evil and trying to run your body without carbs. In some ways it’s the exact opposite – it’s about sparing the glucose you do have. It’s about getting your body to do what it is designed to do under usual evolutionary conditions – burn fat and have enough energy to move all day and/or make short intense bursts. Becoming an efficient fat burner allows you to do just this.
Carb burners v Fat burners
If your metabolism is set up to predominately burn carbs, then you’ll most likely have many more highs and lows throughout the day energy wise. I call the lows “falling off the glucose cliff”. That’s when your glucose dependent brain cries out for more fuel – in the form of simple carbs usually. The cycle continues. If that’s you, then this blog could change your life for the better!
There are many plausible or proven health benefits here to. There is the obvious one of easily being able to control your weight. But far beyond that is reducing the damage high sugar, and high insulin, and sugar burning (glycolysis) do in your body. All of these are inflammatory and cause oxidative stress. These are the causative mechanisms behind chronic disease development including heart disease and stroke, diabetes, cancer, and brain (dys)function.
Fat burning in endurance exercise
One lab-based method we use to measure fat burning vs carb burning is the respiratory exchange ration (RER), also known as the respiratory quotient. This is the ratio between the amount of carbon dioxide exhaled and oxygen inhaled, which provides an indication of which substrate (fat, carbohydrate or a mix) is being used for fuel. We do this using our breath by breath gas analysis system in our Metabolic and Exercise Science Clinic at the Human Potential Centre at AUT Millennium Campus.
The RER varies between 0.7 (100% fat burning) through to ≥1.0 (100% Carb burning). A ratio of 0.85 has been labelled the metabolic efficiency point, when the body burns half of each. We try to determine what exercise output can be maintained for half and half. Bear in mind that everyone will eventually burn 100% carbs if the exercise is intense enough, but the higher the intensity at which fat is still the predominant energy source the better. However, what we are most concerned with is the ability to burn fat at rest and at lower to moderate intensities of exercise. This is great for weight loss. It’s great for health. But it’s also great if you are an athlete trying to do longer distance events like the Ironman triathlon.
We recently had a high level triathlete in our lab. We measured his RER before and after a 10 week training block going into this year’s Ironman NZ. We also transferred him to a low carb high fat (LCHF) diet for the period of that training. He was training about 20 hours a week and came in to the 10 week block relatively fit, albeit slightly heavier than he wished.
Some stats:
- Start weight 86 kg, post weight 78 kg. Good weight loss while reporting eating until full. No deprivation of food or calories if needed. Reduced calorie consumption on long training sessions. Few if any gels or sports drinks.
- Pre RER @ 270 W bike = 0.93, post RER @300 W = 0.82. This translates to a change in fat utilization from 23% of fuel to 60% of fuel at the same power output, for a lighter overall weight (power per kilo was also increased).
- Metabolic efficiency point (50/50 fuel use) improved from 180 W to 300 W. This shows the massive increase in efficiency we saw with a switch to a LCHF diet.
If you know anything about endurance training and racing then you’ll know that these results are outstanding. To the point of being spectacular. The limiting factor in longer races is not maximal output, but how fast you can go while conserving muscle and liver glycogen (carbs). You need to maximize your fat burning and preserve your very limited supply of carbs as much as possible.
Most athletes try to get around this problem by eating extra carbs during training and racing. This can work to an extent, but perversely raises insulin and shuts down your body’s ability to burn fat. It’s almost impossible to eat and digest enough carbohydrate to actually race these events well. You need a good degree of fat burning.
Anyway, this illustrates what can be achieved with a LCHF diet; good, effortless weight loss and spectacular performance gains.
If you’re not an athlete, and I’m assuming most of you are not, then the same principles still apply. We can hook you up to the gas analysis system and determine your “metabolic efficiency” at rest. We can assess just how much of a carb burner you are and we can track your progress if you decide to become a fat burning machine through a LCHF diet.
Fat adaptation v ketosis
There’s a special type of low carbohydrate diet called a ketotic diet. I want to explore that in the next post. Stay tuned.
Why some people stay skinny and others get fat
What I want to put forward today is that there is evidence for two distinct modes of human metabolic state. One is being “fat adapted”. That is, a state where the hormone insulin is well controlled and the body is able to access its stores of fat as a primary source of fuel. This, I contend, is the normal human state. The complex interaction of cells, hormones, enzymes and much much more is in balance. We homeostatically maintain a desirable body weight by self-regulating inputs and outputs. In this state, if we over-eat, we will compensate and burn it off. And vice versa if we under-eat. The mechanisms are complex and not all are well understood. It’s at least a great starting hypothesis. Good science is needed to nail down the whole mechanism but putting together animal and human evidence points to this. This is fundamentally why the “calorie is a calorie” dogma that has plagued nutritional science for the past 40 years is wrong.
When you are “fat adapted” you can easily utilise fat, you have less craving for simple carbs and, most importantly, insulin is well controlled.
However, when you continually eat large amounts of carbohydrates, especially simple refined carbs, then the second mode of human metabolic state results and the body becomes what I have decided to term “metabolically dysregulated”. Others have used the term “metabolically deranged”, but I find that a little too emotional! The mechanism is simplified as follows:
- The body has to continually deal with large loads of dietary carbs.
- It does this by producing insulin, a storage hormone which shuts off the ability to burn fat as a fuel source and get carbs into cells. Some will go into muscle cells (especially in an active individual); some goes into the liver; but if the muscle cells and liver are full, which they often are because they have a limited capacity and people often expend very little energy, then the carbs are stored in fat cells. That’s the basic mechanism for the storing of fat. Insulin also drives extra fat into fat cells too. That’s it. Simple. Insulin makes fats cells get bigger. Without a rise in insulin, there is no easy mechanism for this process.
- Insulin also blocks an important hunger hormone called leptin. Leptin is secreted by fat cells and signals to the hypothalamus in the brain that the body is not starving. By blocking this hormone, insulin is effectively block the “off switch” for hunger so we over-eat.
- Insulin also down-regulates (the process by which a cell decreases the quantity of a cellular component) the pleasure hormone dopamine’s receptors in the brine. This is what gives simple carbs their addictive quality.
- Insulin also down-regulates sympathetic nervous system activity resulting in a reduced propensity to expend energy through both incidental and purposeful physical activity.
- It’s a downward spiral as you get fatter and less regulated and continue to bombard the body with large doses of dietary carbs. You become more and more insulin resistant, both at the muscle and liver cell level. In other words, you need more and more insulin to get the carbs into the cells. Insulin is permanently high. So your cells become more existent. You are always storing fat, never burning it and a state of hyperinsulemia (high insulin) ensues, even when you are not eating. You become fatter, especially around your central area (visceral obesity), which drives more inflammation and increased insulin resistance. Oh boy….!
- Eventually, the beta cells in the pancreas which produce insulin start to fail and you can’t manage your blood sugar levels at all. That’s Diabetes. Constantly high blood sugar is toxic to all parts of the body it touches, and it touches everything of course.
So that is what I call becoming metabolically dysregulated. It is caused by lots of simple dietary carbs. It’s a pandemic. It’s because we have a food supply choked full of processed carbs. And even worse, our medical advice is to go low fat. Low fat, by definition, will mean high carb for the body. More on why in later blogs.
So that’s the dietary choice you have in my view. Eat whole unprocessed foods; low carb, leafy vegetables, moderate protein, high fat and you will avoid the insulin peaks and eventual dysregulation described above. Eat the carbs, send insulin way up and suffer the consequences of metabolic dysregulation. Fat burning shuts down,energy out shuts down. Fat storage goes up. Because energy out is synonymous with quality of life, you feel crap. Being the best you can be has a central requirement of being metabolically well regulated. That’s why I am so interested in nutrition.
Thanks to Helen Kilding for her help with this blog
Fat airfares – what’s fair?
![photo[1]](https://scienceofhumanpotential.files.wordpress.com/2013/04/photo11.jpg)
OK here it is for real at last. We’ve been talking about it for a long time long. The whole airline business comes down to dollars and sense. It’s competitive, and every extra kilo costs extra fuel and aircraft wear and maintenance. Business is business, someone has to pay, and it really comes down to the customer in the end. If you are fat, you should pay more. You’ve eaten too much and moved too little. You gluttonous sloth, you should have tried harder.
Samoa Air now charges by the kilo. You’re an undernourished kid, cool – its very cheap. You’re an obese adult with a bit of luggage. Get you credit card ready. Hopefully it won’t be declined. Hopefully you haven’t put on any weight when they check/weigh you in.
On first pass, as a lean member of society, I agree with Samoa Air. I want to pay less because I weigh less. Why should I subsidise some 200 kg super beast?
And, Samoan Air isn’t really the first to do this. The reality for many morbidly obese people is that there is no way they can travel on a conventional commercial aircraft in a single seat. They end up having to pay double to fit themselves in. It’s simple physics right? No way to fit an incompressible mass into the volume of that seat.
OK, so what this really comes down to is what I want to spend the next few blogs and more on. What is obesity? Why does it happen? Why has it spiraled out of control everywhere? Who should be responsible for fixing this problem? How do we fix it? Is it even possible to fix it?
Back to Samoa Air. Their CEO describes it as a positive health promotion strategy. “This is the fairest way of travelling,” he told ABC Radio. “There are no extra fees in terms of excess baggage or anything – it is just a kilo is a kilo.
“When you get into the Pacific standard weight is substantially higher [than in south-east Asia] but it can be quite diverse. People generally are becoming much more weight conscious. That’s a health issue in some areas. It has raised the awareness of weight.”
Really? A health promotion strategy? Seriously? If only they knew that weight was an issue then they’d be thinner? I doubt there is anyone who wakes up and wants to remain obese. Has anyone seriously ever woken up and said to themselves “today is another day to get fat, bring it on!”
The debate centers on whether people are fat because they eat too much and move to little. This is conventional obesity wisdom, that a calorie is a calorie, and the only way to become obese is to eat too much. By definition, you cannot defeat the laws of thermodynamics. Therefore obesity is caused by gluttony and sloth. The cure therefore is obvious, raise awareness, tell people to get off their arse (move more) and eat less. Problem solved.
This is what drives most of public health effort around obesity, as well as the commercial and ethical response.
Except, we’ve already thought of that in public health, and it doesn’t work.
It doesn’t work, because it’s wrong. Straight wrong. The real problem is more complex and deserves your attention. It deserves your attention because no matter how lean you are, you too will at some point in your life have trouble controlling your weight. You will almost certainly have your life affected because others close to you struggle with their weight and the chronic disease being obese brings with it.
Let’s put out the alternative hypothesis. Obesity is a disease of excess fat accumulation. It’s a metabolic disorder, or at least metabolic dysfunction. Sure, gluttony and sloth are there. But they are symptoms, not causes. This metabolic dysfunction is caused by hormones. Those hormones are complex, but primarily relate to insulin and leptin.
Put simply, when insulin is raised by excessive loads of simple, refined carbohydrates you turn off fat burning and promote fat storage. Insulin blocks leptin – the off switch in the brain. Insulin down-regulates dopamine, the pleasure neurotransmitter in another part of the brain. You think you are starving, you crave more, and you move less. Gluttony and sloth symptoms, not causes. All extra energy is stored as fat. You can’t burn fat. You feel lethargic and tired. Your body goes into storage mode. It’s a great mode if you are harvesting late summer and have a winter or famine to survive.
We are coming back to this mechanism in way more detail in later blogs, don’t fret!
So here’s my bottom line. Obesity isn’t the fault of the individual. It’s the fault of the food supply. It’s the fault of bogus dietary guidelines that promote low fat, high carb diets. It’s the fault of society as a whole and we need to deal with it with science that hits the mark.
Science to date in nutrition hasn’t hit the mark. More to come on that too.
So that’s the debate. How do we deal with obesity? Samoa, one of the fattest countries in the world has started by putting some of the burden on the victims, not the perpetrators.
Am I right? What do others think? Here’s a reaction from a good friend of mine today. He’s very well educated and a great thinker.
MC “I am not so sure there is anything weird in this. Now days, user pays underlies almost every aspect of our lives – and certainly every aspect of discretionary private spending (with limited exceptions such as where it is economically rational for a company to charge customers on the basis of a cross-subsidisation methodology). With any air transport, weight is everything – the more something weighs, the more fuel gets burnt, the more it costs. We accept that in the context of cargo. Why not people? Because it is “unfair”? Really? Airlines work out fares based on average weight. Any given passenger is either above the line or below it. If you are below it, you are subsidising those who are above it; if above it, you are being subsidised. It makes no sense to say that big people are being punished or treated unfairly if they are charged a fare that reflects the greater cost to the airline to transport them. What is unfair is that those passengers who are below the line have to pay more to travel than they otherwise would have to because there are fat people who also want to travel.”
From the NZ Herald
“Absolutely, but as long as you get the equivalent seating space to go with the cost. You pay more, you get more.”
and
“Being attacked by an obesity expert and community leaders as insensitive and lame……
if people want to use those word’s ‘insensitive and lame’ they are just enabling obese people to think that being overweight is ok, and it’s not, it’s unhealthy… it’s nothing else but just plain unhealthy.
You go Samoa airlines you rock. It is a good thing to pay by weight….. you have to if you are posting a parcel don’t you? BTW I am a few kilos overweight.”
I had trouble finding anyone except the “lame obesity experts” sticking up for the fatties. Look, obesity is a massive issue (pun intended). It’s something we haven’t been able to sort. The science is becoming increasingly obvious, but the practice of helping people isn’t doing the business. It’s time for a new approach. Let’s see what actually works.
Stay with the blog and we’ll find some solutions that help us be the best we can be.
The structure of great communication
This is a great TED talk by presentation guru Nancy Duarte. Her ideas about speaking are what you get given when you are invited to do a TED talk. It’s a really powerful and simple analysis of great speeches in history including Martin Luther King’s I have a dream speech and Steve Job’s IPhone launch speech in 2007.
Great communication is of course essential to changing the world. It is essential to any good idea. Without great communication, great ideas are lost. Mediocre ideas can flourish because of great communication. That’s such a shame on both counts. The good news is that this is totally learnable. I did it myself in my TED talk which I’m pretty proud of.
The basic idea is that great speeches all have the same structure – a shape which describes how the world is, and then switches back to how it could be. It always ends with the “new bliss”. It pulls the audience between what is and what could be – the powerful idea you have of “the new bliss”.
Enjoy the video.
Be the best you can be
(pic: the entrance to AUT Millenium where I work)
I’ve wanted to start a blog for quite some time now. The trick is to get the technical skills together well enough to actually know how to run one and do it regularly. Well, I’m just about there.
What will I blog about?
I am really interested in the science of how we can be the best we can be. This crosses disciplines such as biology, medicine, pubic health, and productivity management. The cornerstones are nutrition, exercise, sleep, neuroscience, psychology and well-being. I’ll be covering these topics under the broad heading of the Science of Human Potential (the name of this blog).
I’ve been interested in human health and performance for my whole career. I started in psychology then into sport and exercise psychology, then into public health especially physical activity then obesity.
There have been some twists and turns along the way which might help to give a view of why I do what I do and where it can go.
About me
Sport and exercise has always been a massive part of my life. From an early age I played rugby union, learned to sail and race, and eventually ended up in the high school rowing squad. Rowing at my high school had no room for anything but high performance. So I was introduced to this at age 13. From there we won national championships most years. The combination of the sheer physicality of the sport and the team work and individual excellence required both mentally and physically really defined my teenage years and who I could become as an adult.
Being fit and involved in some sort of high performance activity has been part of my life since then.
I finished bachelors, Honors, and doctoral degrees in psychology at the University of Auckland by 1994. At the same time I had got into triathlon as a sport. I ended up racing semi-professionally. That’s code for “was never quite fast enough to earn a decent living, so had to supplement prize money income by working“. In the end I raced professionally in several world championships in long course triathlon, ironman and duathlon. That was great fun, and the skills and work ethic I have learned from triathlon are important to me.
The extra benefits from the high performance sport world, especially triathlo,n include:
- I met my wife Louise because of triathlon. She ended up also as a professional triathlete, a better athlete than me. We’ve been married since 1995 and have three boys – Sam, Jackson and Daniel. Louise also started Vitality Works, a workplace health company acquired by Sanitarium in 2012. Vitality Works has allowed both of us to benefit from a huge amount of professional and personal development in health and well-being.
- I figured out early that a high performance life is just as much work as a low performance life, so you may as well take the high performance life. It just requires a bit more work up front, but frankly you avoid work later and you get more choices.
- I have the skills to stay fit and enjoy maximizing my biology for my own personal peak performance.
- I still get to compete at a reasonable level in triathlon and running. This is cool because the age group triathlon and running groups are really fun, and you get to hang out with people of a similar performance, health, and happiness mindset.
My academic career began with part-time teaching in the Psychology Department at The University of Auckland during my PhD tenure. I moved to Australia (Central Queensland University in Rockhampton) and worked in the School of Psychology there for nearly 10 years. Most of our spare time then was dedicated to triathlon training and racing with Louise. I wasn’t going fast or far in the academic world at that point. Enter Kerry Mummery.
Kerry Mummery is now the Dean of Physical Education at the University of Alberta. He really mentored and started me on the journey to becoming a decent academic. We worked on several physical activity and health projects together. The most notable was 10,000 Steps. This started as a whole community project and morphed into a nationwide program which is still running successfully today.
This was the entrance into public health proper for me. I started at AUT in 2003 after the birth of Jackson our second son. Back in Auckland and into a new country with plenty to do. That’s when things really took off. I had the good fortune to have several great staff members and PhD students under my guidance. Almost all of these are still with me.
The highlights in the last decade are:
- Working with dozens of talented doctoral and masters thesis students
- Being highly successful in obtaining research grants and funding. This is the life of an academic and you live and die by this success. We are up over $20 million in funding.
- A solid and respectable publication record. Ditto above. Important for gauging success. But by itself is unlikely to put much of a dent in the universe.
- Being involved in Vitality Works. This has put a dent in the universe and allowed me to develop more formally into peak performance, well being and neuroscience.
- Being the youngest full professor around for a while. That wore off as I aged!
- Moving our work beyond physical activity into obesity, well-being, productivity, and nutrition/weight loss. Most recently the work we are starting in metabolic efficiency and weight is likely to put the biggest dent in the world.
- Starting the Centre for Physical Activity and Nutrition and eventually morphing that into the Human Potential Centre at the new Millennium Campus.
So that’s where I’m at. Where I want to go now, and with this blog, is to explore the science behind what helps us “be the best we can be.” It’s an emerging and multidisciplinary science. Let’s go!
The Science of Human Potential 