Low-carbohydrate diets for athletes.

Grant Schofield


In this presentation from the NSCA’s 2013 Personal Trainer Conference, Alan Aragon and Jeff Volek discuss low-carbohydrate diets for athletes.  It has quite a bit of science and is an hour, but its a great little talk with some good information.

Comparing LCHF and the Mediterranean diet

Spot the difference

By Helen Kilding and Grant Schofield

We’ve been hearing quite a lot about how healthy the Mediterranean diet is.  So what is it, and how does it compare with the Low Carb, High Fat (LCHF) approach that we talk about on here?  How different are they and why would you choose one over another?
Let’s find out.
The traditional Mediterranean diet is characterised by a high intake of olive oil, fruit, nuts, vegetables, and cereals; a moderate intake of fish and poultry; a low intake of animal products like dairy, red meat, processed meats, sugar and sweets; and wine in moderation and consumed with meals.
The LCHF diet is characterised by a high intake of natural fats (including olive oil, but also other healthy fats such as butter and coconut oil), a similarly high intake of vegetables, but limited fruit and no cereals. Why limited fruit? Fruit is nature’s candy, with a medium sized apple containing the equivalent of 3 teaspoons of sugar. Sure, in it’s natural form, fruit is a good source of fibre and some vitamins, but so too are vegetables, and with less of the sugar hit. 
And why no cereals? Well despite what we’ve been lead to believe, there is no good reason to eat cereals, even wholegrain. The fibre argument and the vitamin and mineral argument just don’t stack up – a plate of salad or veggies packs a much bigger and better fibre and vitamin/mineral punch than any cereal. And whether we need more fibre in our diet is debatable anyway. But cereals are cheap and highly lucrative. The corn industry has a lot to lose if/when the truth gets out. As Christine Cronau (author of The Fat Revolution) nicely describes, “a breakfast of eggs and butter is packed full of Vitamins A, B, D, E and K, along with iron, zinc, calcium, lecithin, iodine and more. Adding some unrefined salt adds a further 84 minerals and a fried tomato a healthy dose of vitamin C”. Beat that cereal!
The fact is humans are not adapted to consuming cereals and they are full of toxic anti-nutrients (lectins, gluten and phytates) that we don’t have the ability to deal with. Lectins bind to insulin receptors and the human intestinal lining and cause leptin resistance, which as regular readers of this blog will know, accelerates metabolic syndrome independently of obesity. Gluten (found in wheat, rye and barley) might be even worse and certainly is more widely known. Around 1% of the population are celiacs (completely intolerant of gluten) but it’s not just celiacs who suffer the damaging effects of gluten. And finally phytates, make the very minerals that whole grains and cereals supposedly provide us with, bio-unavailable. Awesome!
But getting back to our comparison, a moderate intake of fish and poultry is common to both diets, as is a low intake of processed meat, and wine in moderation. So the last big difference really is in the red meat, cheese, eggs and sugar. Whereas the Mediterranean diet supports low intake of all four, LCHF promotes unlimited consumption of meat, eggs and cheese and no consumption of sugar.
The health concerns around meat and eggs, particularly in relation to cholesterol, are unfounded and indeed animal proteins and fats, like eggs and butter, contain many of the nutrients missing in modern Western diets. With the Mediterranean diet, around 25-35% of calories come from fat (8% or less from saturated) compared to around 70-80% on LCHF. With the latter, the body learns to use fat for fuel instead of sugar (read more about fat adaptation here). If fat intake is too low, this cannot occur, so regardless of whether you are carbohydrate sensitive or not, if you want to become a fat burning machine, for endurance performance, weight management or improved cognitive function, LCHF rather than the Mediterranean diet is the way to go. Remember though, fat intake should only be high if carb intake is low – high intake of both is not OK! 

Can you be a healthy endurance athlete?


I’ve been getting quite a few questions about triathlon and other endurance sport training and racing.  Even in our own research group, there is a lot of debate and questions about what and how, especially regarding supplemental carb use.

I think it comes down to understanding that ‘high performance endurance athletics’ and ‘health’ are not always the same thing.  I might even go as far as to say that they are mostly mutually exclusive in the long run.

That’s different from doing endurance events and being healthy – I believe that is possible.

Most of my friends are not going to like hearing this…and after a life of pursuing carb-fuelled high performance endurance, why have I changed my mind?  And what should you do if you like being involved in endurance sport and exercise but want to maximize your health and avoid things like heart damage and self-oxidizing yourself into early aging.

I’ve been an advocate recently for the polarized training approach – where you spend most of your time doing very easy aerobic, fat burning exercise, and just a short amount of time doing very  high intensity training.  You try and avoid that middle chronic cardio zone.

Case study 1: Joe McQuillan, endurance exercise physiologist and low carb high fat (LCHF) proponent.  He is happy enough himself to be on a LCHF diet because of the energy and weight benefits, but he’s not convinced that a polarized training approach (also known as an 80/20 approach) generates any sort of high performance for competitive endurance athletes.

We just finished a long discussion about this where Joe points to the “optimal” training points for endurance performance.  Here’s his note below on this.

Grant, this modified table (below) is from Racing and Training with a power Meter by Coggan and Allen. All I have done is arrange the outcomes by way of 1st and 2nd contribution to enhancement of that outcome. FYI L3 is tempo, L4 threshold, L5 VO2max, L6 anaerobic (<3 mins). Nowhere on the list is L2, for most it falls as the 3rd most important zone to contribute changes to an outcome of X. This does not detract from the fact we need to do L2 exercise and a lot of it for base work, but within L3/L4/L5 sessions we spend time in this (L2) zone, + warm-up and cool down from interval training increases this by default. I think in certain phases for a road cyclist and 1/2 IM/standard dist triathlete a 50/50% <L2/>L2 is likely.  

 I don’t see 80/20 as a valid method for enhancing performance at L3/L4 racing (I also saw this recently appear as 75/25).

 Expected Outcomes

1st Priority

2nd Priority

Increased plasma volume (L4 & 5)



Increased muscle mitochondrial enzymes (L3 & 4)



Increased lactate threshold (L3 & 4)



Increased muscle glycogen storage (L3 & 4)



Hypertrophy of slow twitch muscle fibres (L5)



Increased muscle capillarization (L3)



Interconversion of fast twitch muscle fibres (type IIb -> type IIa) (L3 & 4)



Increased stroke volume/maximal cardiac output (L4 & 5)



Increased VO2 Max (L3 & 4)



Increased muscle high energy phosphate (ATP/PCr) Stores (L6 & 7)



Increased anaerobic capacity (“lactate tolerance”) (L6)



Hypertrophy of fast twitch fibres (L7)



Increased neuromuscular power (L3)



In other words, the best race results for an athlete can’t easily be obtained from mostly easy training with some occasional harder stuff.

Is Joe right? Well the more of the higher intensity training you can get AND adapt to then the faster you will probably end up going. This is similar to what Mark Sisson talked about in his blog this week – it’s a matter of time frames and perspective on performance. Long-term health eventually matters to long-term athletes too.

The thing is that short-term or even medium-term maximum performance doesn’t take into account overall wellbeing and health – which applies long-term both to elite athletes and weekend warriors.

There is only so much moderate to high intensity training you can take.  So my feeling is that most people should be very careful about overdoing this.

Believe me, I have been there done that as far as overdoing it is concerned. It’s still something I constantly struggle with – exercise makes me feel good and I like so many aspects of it, including the social.  But the toxic effect of too much intense exercise is something I have to try and avoid for my own good.

This of course means that I won’t be competing with and beating people who I likely could, simply on the basis of our pre-training physical abilities.

That’s a bummer, but that’s the way it goes.  Some guys will always smash themselves up a bit, optimize their performance, choosing to neglect their long-term health. They will be the ones on the age group podium.

Should we celebrate this? Probably at the Olympics and world championships we enjoy seeing what the limit for humans is.  But, in my opinion, that shouldn’t be what non-professional athletes celebrate. If you want to do that, then do it in small controlled amounts and take a break.

Health, as I have written about previously, is about the application of stress and your adaptation to it. Too much stress is toxic. My opinion is that 20 hours of triathlon training a week is likely to be too much for most people who are working full time and might have other commitments – e.g. family, work, etc.

I guess that’s why you see a good deal of podium triathletes at triathlon age group world championships are professional coaches or independently wealthy and not working.  It’s only under these special conditions that you can tolerate the training stress and recover from it. Even then, that isn’t the optimal health outcome.

So if you’ve made your personal decision about endurance sport and health – and it is about personal health and wellbeing first, performance second – how should you proceed?

The balance between health and performance?

Case study 2: Julie, an older female triathlete

My goals are to get and hold my weight to or just under 60 Kgs and get my running improved. Current weight 61 Kgs. Generally in a tri I struggle to keep my 10km run under 55 mins. For my age group I am usually in the first 20% of the swim 10% in the bike and 50% with the run. I end up with a final placing in the first 5.

 I followed a schedule of about 18 hours training a week leading into the Auckland ITU (world champs). Aged 59 and came 10th.

 I will look to start Tri’s this summer. I have had a year off after 10 years competing.

Here’s my suggestion – give or take for the best balance between stress, enjoyment, health, weight management and energy.  Just a guide and flexibility is important.

First: Nutrition – Accessing and using aerobic lipolysis (fat burning) during the bulk of your training is crucial.  It produces less oxidative stress, tires you out less, requires less effort, and your brain and body operate more efficiently.  For this I suggest a whole food Paleo style diet with a degree of carbohydrate restriction – preferably off all sugar and grains. The amount of carb restriction depends on your tolerance to carbs and exactly how much glycogen you are burning in training. Dr Peter Attia has recently written a nice piece on calculating this. I prefer the full low carb high fat approach in a whole foods framework. That works well for me.

Just to reiterate, you need to get the nutrition right first.  No amount of training properly can make up for setting yourself down the sugar burning/addiction pathway.

Also, remember the exercise isn’t the thing that helps you make your goal weight – the nutrition does this.

Second: Training – I suggest capping things at 10 hours a week, maybe 12 if you have to. Remember it is adapting to the training that is important.  You won’t race at your absolute best, but you will be most of the way there. Exercise is a potentially toxic stimulus to your body. You want just enough in the context of the rest of the stress in your life to be able to adapt to it. Better under-doing it than over-doing it.

The bulk of the training is easy aerobic L1, L2, occasionally a little L4-5 where it can’t be avoided (going up a hill on a bike).  I’d do virtually all sessions in this zone, except 2 maybe 3 a week where I’d do some very short and very hard interval sessions like the ones below.


  • Run track 10 by 1 min with 1 min rest.
  • Bike: 2 by 6 by 40 sec hard out, 40 sec rest
  • Swim: 10-15 by 50 m

This makes it very easy to design a program, you spend 10-12 hours in a combination of swimming, biking and running at easy aerobic pace.  You throw in very short sessions when you feel up to it, where you maximally hit out.

That, in my opinion, is the way to health.  It’s not the way to the best possible race performance though.  Your call.

Thanks as always to the super diligent Helen Kilding for her editing

Is exercise damaging my heart?


Recent high profile athlete cases of heart problems, especially arrhythmias, has had many of us asking several questions about the endurance exercise we do on a regular basis. These include:

  1. What’s the risk?
  2. Is it linked to the actual exercise or something else?
  3. What might you do to mitigate the risk, but still get the benefits of being fit?

It really seems that the evidence is starting to stack up from case studies, to epidemiology, to mechanisms. Let’s explore the issues.

1. What’s the risk?

A recent study published in the European Heart Journal shows several things. Actually, there is a really great comment in a blog by cardiac specialist Dr John Mandrola.

To sum up (that is, to skip the abstract and comments below and get straight to the next point), there is strong associational evidence that hard and prolonged endurance exercise may damage the heart, which results in sometimes serious heart problems. The overall risk is doubled compared to non-athletes, but the overall risk is still only around 2%.

Here’s the abstract of the study…

Aims We aimed to investigate the association of number of completed races and finishing time with risk of arrhythmias among participants of Vasaloppet, a 90 km cross-country skiing event.

Methods and results All the participants without cardiovascular disease who completed Vasaloppet during 1989–98 were followed through national registries until December 2005. Primary outcome was hospitalization for any arrhythmia and secondary outcomes were atrial fibrillation/flutter (AF), bradyarrhythmias, other supraventricular tachycardias (SVT), and ventricular tachycardia/ventricular fibrillation/cardiac arrest (VT/VF/CA). Among 52755 participants, 919 experienced arrhythmia during follow-up. Adjusting for age, education, and occupational status, those who completed the highest number of races during the period had higher risk of any arrhythmias [hazard ratio (HR)1.30; 95% CI 1.08–1.58; for ≥5 vs. 1 completed race], AF (HR 1.29; 95% CI 1.04–1.61), and bradyarrhythmias (HR 2.10; 95% CI 1.28–3.47). Those who had the fastest relative finishing time also had higher risk of any arrhythmias (HR 1.30; 95% CI 1.04–1.62; for 100–160% vs. >240% of winning time), AF (1.20; 95% CI 0.93–1.55), and bradyarrhythmias (HR 1.85; 95% CI 0.97–3.54). SVT or VT/VF/CA was not associated with finishing time or number of completed races.

Conclusions Among male participants of a 90 km cross-country skiing event, a faster finishing time and a high number of completed races were associated with higher risk of arrhythmias. This was mainly driven by a higher incidence of AF and bradyarrhythmias. No association with SVT or VT/VF/CA was found.

Dr Mandrola says the following:

It’s pretty simple: extreme endurance exercise, done over the long term and with great intensity, increases the risk of arrhythmia. There’s no refuting this strong association. These observations are both plausible and consistent with prior studies.

There should be no surprise when an endurance athlete shows up with atrial fibrillation or some other arrhythmia. We are not surprised when masters-aged athletes suffer from other inflammation-induced maladies, like overuse injuries, heart attacks, infections, and even divorce; why are we surprised they get AF?

But context is important. Previous studies have shown Vasaloppet finishers enjoy lower overall mortality. They smoke less, carry less body fat, and report better eating habits. This bolsters the idea that the lifestyle of endurance racing confers good overall health to most participants. Exercise is good. That observation remains unchanged and unchallenged. In the US, we would do better with an epidemic of over- rather than under-exercise.

It’s also important to emphasize that association is not causation. We don’t know whether excessive exercise alone caused the arrhythmia episodes. There are too many possible confounding variables to make a causation link.

[Grant – true, but see below, there is mounting evidence that it is exercise that causes this]

And . . . just because intense and long-term endurance exercise increases the risk of arrhythmia does not mean athletes should avoid a sport they love. These studies don’t tell us to recommend against endurance exercise. They simply inform both doctor and athlete of possible consequences. There are always trade-offs.

As physicians and teachers, knowledge of the association between chronic inflammation and disease might help us give better advice to our athletic patients. My guess, and it is just a guess, I am no coach, is that the same things that help an athlete avoid AF might also make them faster. Do you think getting adequate rest and recovery improves VO2max? Do you think being content with something less extreme than an Ironman or cross-country ski marathon might be antiarrhythmic? What’s wrong with a fast 10K?

[Grant – see below – I think its more about changing nutrition and training methods, but more work needs to be done]

2. Is it linked to the actual exercise or something else?

This is an important point because the study above is only correlational. However, there is enough mechanistic evidence developing to show that the actual exercise itself might be the cause. A study in forty endurance athletes showed significant signs of right ventricular damage following an endurance event lasting between 3 and 11 hours.

The authors conclude that “intense endurance exercise causes acute dysfunction of the RV, but not the LV. Although short-term recovery appears complete, chronic structural changes and reduced RV function are evident.”

3. What might you do to mitigate the risk, but still get the benefits of being fit?

Overall, I would say that these studies and the broader developing evidence shows that excessive and extreme endurance training increase your risk of heart problems. Like anything else, that’s a population measure. What it actually comes down to is whether it affects you or not. That’s binary, not probabilistic. You will either develop a heart problem or you will not.

So what do you do? If you, like me, like the exercise; you understand the benefits are many and done well outweigh the risk, I would say reconsider how you train. I wrote about this is in a previous blog on polarised training and fat adaptation. Both are likely to reduce the oxidative stress on the body and the time you spend in the prolonged hard cardio zone.

Remember, loads of oxidative stress, glycogen burning, and reactive oxygen species has numerous effects on the body; especially the immune system, tissue damage, and DNA damage. This results in a longer recovery time, more sickness, and higher risks of longer term problems.

Take home messages:

  • Exercise is still overwhelmingly good for you. We have a population epidemic of marathon sitting, not marathon running.
  • But…exercise taken to extreme might damage your heart, and you won’t know you have done damage until it’s too late.
  • New training and nutrition techniques may reduce the stress on the heart and body because you go slower more often, and only occasionally really fast (and probably get fitter), and you burn mostly fat (with your heart using ketones as a fuel which it prefers).
  • So, stop flogging yourself at training, eat less carbs – especially sugar, and eat more healthy fat. You might even be faster! You also certainly will be helathier.

How do I get fat adapted and train for triathlons?

Hi Grant,
I met you on the weekend at the New Zealand Society of Positive Psychology after the morning workshop when you showed a group of us around your building. I asked you, as a ‘fellow triathlete’, about your diet and exercise regime. You directed me to your blog which I read and found very interesting. I have started on the road to a LCHF diet 🙂 So far so good.
I would really appreciate your advice on an exercise programme. Your current exercise programme sounded really interesting – not as grinding or as long as the programme I use. I need a coach – yes I am a needy person! South Island, ideally Christchurch, would be great if the person follows your ideas! I follow my training programmes to the letter – just the way I am. I would be delighted to be part of a research programme if that would be helpful to anyone. I am 60 years old this year and enjoy competing in Age Group Triathlons.
Looking forward to hearing from you.
Hi Jane
Great to hear you have made a start on the LCHF diet. Just some extra (unsolicited?) advice for the adaptation period. If you are sufficiently restricting dietary carbs to around 50 g or less a day, a few things are worth noting:
  1. Your brain will no longer have enough glucose to run purely on glucose for fuel. This means that until your body can re-orchestrate how it can fuel the brain, you will feel crappy. Some people call this the “keto” flu (because you are adapting to a state of nutritional ketosis). The brain will need to use the by-products of fatty acid oxidation (specifically beta-hydroxy butyrate, or BHB) to make up for the lower amounts of dietary carbs coming in. So most people have a period of a couple of days of mental haze. In my experience, if you have a job where you have to actually think, then plan to try to do this phase at the weekend. Training volume will have to decrease too.
  2. It is possible to mitigate some of the symptoms of the adaptation (dizziness, tiredness, brain fog) by supplementing with good quality medium-chain triglycerides (MCTs). These automatically put fats into your body which mimic the ketones (BHB). MCTs can’t be easily stored as fat and are burned intra-muscularly AND in the brain. Coconut oil is very useful for this. Butter has a good deal of MCTs. Other coconut products do too.
  3. Salt supplementation can be important. In the adaptation period many people find themselves getting dizzy due to hypotension (low blood pressure). What is likely to be happening is that the kidneys are dumping sodium to keep the sodium-potassium balance intact. So, eat heaps of coloured veggies to get the potassium up. Salt gets salt up too. We could be talking up to 5 g/day in the adaptation period.
  4. Keeping an eye on dietary carbs is very important as if intake isn’t low enough, you can end up in the grey zone of just feeling crap and never fat-adapting. A few tricks here are to:
    1. Use a computer-based or smart phone diet diary. If you are in Australia or NZ, the best and free one for this is “easydietdiary”. It links to Aussie and Kiwi food databases. A great learning tool.
    2. Over-consuming protein can also trick you out of fat adaptation because once you reach your daily requirements, you turn extra protein into glucose through a process called gluconeogenesis. Depending on activity levels, daily requirement will likely be 1.2-1.5 gram of protein per kg body weight. Again, the easydietdiary, or other food counters, can assist in seeing how you compare to this. I’m not saying you need to count food all the time, just get an idea of exactly what has what. Some foods are surprising (e.g., BBQ sauce = 53% sugar!).
The idea is that once you are fat adapted, your body should prefer fat as its primary fuel source. This has numerous benefits including more stable mood, lack of hunger and cravings, a better night’s sleep, easy weight control, and an ability to easily miss meals and enjoy the benefits of intermittent fasting.
Now, onto training for endurance sports in the fat adapted state. I have moved into a space which we call “polarised” training. A couple of really neat studies (see below) have come out recently which support this type of training over conventional threshold type training. It is especially good for those on a fat adapted diet because with this diet, you simply won’t have enough glucose supply in the liver and muscles to train in the athlete grey zone, where most (triathletes especially) spend their time.
Here’s what we are talking about:
Polarized training = 80%+ time spent in low intensity work, at or below VT1 (very easy), and 20%, or even less, in very high intensity work (above VT2), which means very hard and hurting. The overall training load and duration will be less than the conventional model, mostly because full recovery is required for the high intensity side.
That’s not what most athletes in endurance sport do. What I regard as the conventional model of endurance training is quite a bit of longer endurance work, but also 30-40+, or even more, in the VT2 range or just below. That’s sort of what some people call threshold zone.
In my opinion, and the evidence both mechanistically and experimentally is mounting, the trouble with the conventional training approach is that much of the training is powered by exclusive carbohydrate oxidation. This creates reactive oxygen species (ROS), glycated-end products, and cellular damage. All of these compromise immune system function and create cell level damage. This rolls out as a tired athlete, who gets sick more often, and recovers more slowly. It also means you are predominantly burning carbs for fuel and therefore need to fuel on carbs constantly. That means none of the benefits of being fat adapted. It also means you have to rely on glucose exclusively for fuel in races. This is a very limited fuel supply in longer endurance races, and the supplementation of carbs through gels and so forth can cause serious gastric distress. It’s also just damn hard to keep your weight under control when training and eating like this, at least for some people (including myself), and especially older athletes.
On the polarised training and fat adapted side, you are burning fat for most of your training and not creating the cellular damage and immune system compromise. You are fat adapted and feel great. You stay in shape more easily and the hard sessions are short enough that extra glucose supplementation isn’t necessary.
Here are some links to two recent studies on polarized training v conventional training for endurance runners and cyclists. Great outcomes on less training.
So what does polarised training look like for me? I do mostly easy long runs and rides (read no rush of ego-driven frenzy). When I feel recovered enough to do so, I do a short and very intense session. That could be once, twice or three times a week. It all depends on my life stress and nutrition quality.
Here’s a few examples:
  • Running track: 10 min easy jog, 10 by 1 min hard on the track, walk 1 min recovery in between. This means I get about 325 m round the track and then walk around to the start of the 400 m again. Actual distances will vary depending on fitness and running ability. That’s the session! Total time: 30 min / Total hard work: 10 min
  • Running treadmill: 10 min warm up. Crank the treadmill up to 19.5 km/hr (or whatever speed is hard for you). I do 4 times through 40 sec run, 20 sec rest, 30 sec run, 15 sec rest, 20 sec run, 10 sec rest, 10 sec run, 5 sec rest. I rest for 4 min after 2 cycles through this. This is very hard, but over quickly. You leave the treadmill going at full speed and hop to the side to rest. Total time: 24 min / Total hard work: 10 min
  • Bike road: Ride for an hour on a hilly circuit. Go flat out on every hill, cruise down. Total time flat out: about 20 min
  • Bike trainer: 10 by 2 min, increasing power every interval by 10 watts from about 340 to 400 w. This really hurts. 2 min rest in between and slightly longer if really hurting.
Those are a few ideas of what I like. I would say that people should make their own ones up to suit time and fitness (and how much you like the pain game!). The other thing you do have to do occasionally is some racing and race simulation, which will be more in that threshold sub-VT2 zone. Fine, limit the damage and take some carbs on board for that part. You will need them. The Kreb’s (glucose metabolism) cycle is spinning fast and the dietary carbs won’t spike insulin and turn off fat burning in this zone, as long as you aren’t silly about it.
Enjoy, and happy fat adapting!

What do I actually eat?


Grant Schofield has a chat to a village pig about the pig’s future. The pig listens carefully.

Thanks to everyone who has started following this blog.  Frankly, while I find this stuff interesting and important, I had no idea that it was shared by so many other people.  An academic’s real-life exposure to social media is an eye opener and fun. 3000 hits in a little over a week!

So the main question I have had from people so far is “what do you eat?” and “what about kids?” I think I can talk about both of those, in this and the next post. After all I am me, and I am the father of three boys.

Some background:

I have been active and relatively fit my whole life, including a stint as a professional triathlete. One observation and my main excuse for not being a long lasting and super duper fast professional triathlete, was that I could never get my weight under 85-86 kg.  In fact, when I did my fastest time in Ironman NZ 2001, I was officially entered in the heavy weight “clydesdale” division, where I was 94 kg at weigh in. To be fair, that was at the conclusion of the pre-race pasta party. My time of 9:04 was (I claimed at least), at the time, a clydesdale world record.  I’m not sure there is such a record but it gave me mileage at the time – “world’s fastest fat guy over the Ironman triathlon distance”.

What bugged me though was why I couldn’t get fully race lean. I was eating low fat, high carb.  It was exactly what the experts said I should do.  I could hardly exercise any more.  I was training up to 25 hours a week! In fact, I noticed the same thing when I watched the Ironman in Taupo New Zealand  this year.  Roughly one third of the field is overweight or obese in my judgement.  How can they stay fat doing so much exercise?  Maybe they are LESS fat than when they started?  Or maybe their high carb diet and chronically raised insulin fails to allow fat burning?

Anyway, post triathlon retirement and children arriving I was up over 102 kg.  I was still exercising everyday, eating “healthily” and still fatter than ever and it was getting out of control.  Why was I always hungry? Why did my energy always “fall of a cliff” after lunch? I was trying really hard to NOT be a fat bastard. You can imagine, I do physical activity, nutrition, and obesity research.  You lose street cred when you are fat.

My Solution:  Take up marathon running and starve myself.  This method got the weight off. It also made me sick and injured.  I was especially prone to colds and flu with several every year. I hate flu.

I finally got consistently injured enough to flag the running and take up age group triathlon again. Same results:  weight creeping, always creeping.  When it crept past an acceptable point, I’d starve myself and exercise like crazy.  I’d get sick.

Surely there has to be a better way? Enter, LCHF.

Now: I’m down to my lightest weight since mid-high school.  79 kg, lean, full of energy, and all the  injury and illness has gone.  I’m eating until full, as much as I like.  It’s Awesome.  I wouldn’t have believed this was possible.  But it is.

I started reading all the literature and science in nutrition, which has been part of my broader field for a while.  I have read enough now and experienced enough case work to change my starting hypothesis.

That’s partly why this blog is here.  That’s why I have changed my research and practice direction in physical activity, nutrition and obesity, as well as the broader area of well being. I am now up with the science and we need to do it better.

So what do I eat?

I don’t always eat three meals a day now. I often try intermittent fasting which usually isn’t planned but happens naturally* according to hunger, food availability, work pressures and convenience. For this to be possible is a revelation to me.  I have spent almost all of my life being pretty much hungry the whole time.  If I didn’t eat every few hours I would fall off a glucose cliff and basically become 50% functional.  This is hardly convenient and hardly optimal for a high performance life.  My new way of eating also allows me to easily create calorie deficits to manage my weight if I feel I need to.

*The fact that I can quite often end up fasting accidentally for relatively long periods, while staying mentally sharp and full of physical energy, is an amazement to me.  I’ve spent my whole life doing exactly the opposite.  It’s sort of like the “user manual” for being me has been found.  I am fat adapted and can oxidize fat as a primary fuel source. I can use ketones as a fuel for my brain.  I don’t fall off the glucose “cliff” every few hours.  This is a great place to be in.  It also means you lose the cravings for the sweet food, especially sugar. This is the main benefit most people I know who have moved into this style of eating report. The constant energy and loss of ridiculous hunger every few hours.

I also have the occasional off day or meal when I just do whatever I feel like.  We are all human after all.  I used to plan these for a while and really looked forward to them.  Frankly, now, I can do this if I want but I feel so crappy after eating simple carbs, especially wheat products, that I just don’t bother much.  Again, this is a revelation as my self control in the face of high sugar high carb foods in the past has been completely non-existent!

Here are some typical meals for me:


  • Scrambled eggs with whipping cream and streaky farm bacon from the butcher fried in coconut oil
  • Smoothie made with coconut cream or milk, whipping cream, coco powder and or fresh berries
  • Salmon, avocado and tomato
  • Omelette with cheese and veggies (meat added when I feel like it).


  • Massive salad with lettuce, tomato, capsicum, cucumber, cheese, meat of some sort – fish, chicken, bacon whatever is around, avocado, almonds.  Mix up and add copious amounts of dressing which is home made olive oil and vinegar or mayo.  The dressings have to be made by you, because almost all commercial dressings use hydrogenated vegetable fats – yuck – and are often high in sugar
  •  That’s my “go-to” lunch above.  I lack imagination for lunch according to my family, but that’s the way it goes!  I do have eggs and smoothies for lunch sometimes or something from the dinner/lunch list below.


  • Some sort of meat or fish.  Heaps of veggies (green and red veggies as a rule, cauliflower is also good, avoid starchy ones). I like pork with crackling. This is the time to really appreciate the flavors of fat.
  • Wine, although I am trying an alcohol free month right now because it was getting out of hand!
  • Berries and cream for dessert
  • Low carb cheese cake is a favorite

Other tips and traps

  1. Don’t trim fat. Healthy fats are monounsaturated olive and other nut oils, Omega 3 fish oils, and healthy meat fats (unprocessed red and white meats including beef pork, fish and chicken), as well as dairy fats. Coconut oil is great.  Avoid hydrogenated and polyunsaturated fats, especially in cooking.
  2. Just to reiterate, you have to replace carb and protein calories with something.  The only macronutrient left is fat.  Our ancestors likely coveted fat.  Fat, at least as far as insulin and leptin goes, is metabolically benign.  Carbs are not, especially when they are rapidly absorbed.
  3. Coffee is OK, I use whipping cream not milk. I tend to avoid dairy except cheese of all sorts (yum!) and cream.  Milk can be high in lactose (a carbohydrate). Those who are more carbohydrate tolerant (have an ability to eat carbs without weight gain) can go for full fat milk and a fuller range of dairy. Most kids are in this  category.
  4. Alcohol is a tricky question.  Alcohol is certainly not metabolically benign.  I recommend abstinence during the adaptation period into LCHF. Have a look at this link to explore more about keto/low carb adaptation. Then what you want is a low carb drink if you enjoy alcohol.  I certainly don’t drink alcohol for physical health reasons but I do drink it for social and marital health reasons!  My wife Louise and I spend lots of time sitting on our deck drinking wine and talking.  Great fun!  The active alcohol is called ethanol and is processed in the liver without much effect on insulin, at least not directly. It in fact follows a similar and dangerous path to the liver and beyond.  It’s metabolically active in an inflammatory and insulin resistance-promoting kind of way.  However, that said, we all have our vices, the actual insulin raising carbs in a glass of wine are between 3 and 6 g, depending on the wine and the size of glass (we have big glasses in our house!) so a glass or two is fine. Beers have way more carbs (12-20 g) per bottle and contain wheat that may result in other metabolic effects for some people.  You can get low carb beers of course.  I don’t really care for spirits, as a result of bad youth experiences I think, but if you do use them then it’s crucial to leave out the sugar based mixers.

That’s my wrap.  I’m not perfect and as a normal human fall off the wagon too.  I’m on the 18/21 plan. If there are 21 meals in a week, try for at least 18 good ones, hopefully better.  Let me know your favorite meals and we can post them up.

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!