Never has a topic, not just in ultramarathon running but in
the nutritional world in general been subjected to a generalised
pseudoscientific analysis as that of diet.
It is of course very natural for every athlete to
contemplate and analyse every aspect of their training in order to improve
performance and that includes diet. The chemicals that you put into your mouth
ultimately translate into performance and it is natural to analyse what is the
optimum combination of these chemicals that lead to a best performance in an
event. But diet is not just about optimum performance; it is about generalised optimum
health as well. The two are closely related as without optimised health there
can of course not be optimised performance.
I will argue a case that a diet for optimised health is
indeed a diet for optimised performance but that the diet during that optimised
performance is actually radically different from the diet that lead to that
optimised performance.
In the introductory sentence I mentioned that the subject of
diet is one that has been subjected to more pseudoscientific (bad science) analysis
than any other, not just in the world of ultra-running but in the dietary world
in general. Body biochemistry is hideously complex with interplay of literally
thousands of biochemical pathways, a symbiosis of which is a long way from
being fully understood. It would be fair to say that at best we only partially
understand these mechanisms and at worst completely misunderstanding them
leading to practices that not only do not lead to optimum performance but that
actually harm it and our general health in the process. I am not saying that
these authors set out deliberately to mislead but when there is such a large
interplay of a ridiculous number of parameters it is frighteningly easy to
arrive at incorrect conclusions.
Bad Science
In writing this piece I will draw attention to the fact that
I have a Ph. D. in science (Physical Chemistry). I do so, not to boast about my
academic credentials but to draw attention to the fact that I am trained in the
scientific method and more importantly I am trained in spotting bad science.
Diet is certainly not my academic specialism but as an ultra-endurance athlete
it is one that I have a great deal of interest in and one that I have studied
extensively. Perhaps the most important thing I have discovered from my
research on the topic is in spite of huge amounts of data that actually exist there
is a huge lack of what I would describe as hard understanding on the topic and
the subsequent substitution with what is otherwise known as bad science. And
for those of you that prefer a bit of straight talking; that’s “Bullshit” in
American English or “Bollocks” in British English by the way.
The term “Bad science” which has been popularised in Ben
Goldacre’s excellent book with just that name “Bad Science”. (http://www.badscience.net) It does not
mean for one minute that these conclusions are actually wrong. What it means is
that the conclusions have been derived on incomplete data. But before analysing
what we mean by bad science, let’s look at some “good, hard science” and then
make a candid comparison. Newton’s laws on motion can be described as good,
hard science. Newton, about 300 years ago formulated a set of very simple
equations that were able to describe the whole of the then known physical word.
These laws and his equations, whilst not only being very simple were extremely
powerful. They had a predictive nature about them that is fundamental to the
concept of good science.
Describing what we know about diet and ultra-running performance
can indeed be described as bad science. This is not at all surprising as it is
a hideously complex topic and isolating parameters that can be studied in order
to determine their precise effect on performance to the degree of accuracy that
Newton was able to describe the effect that mass has on acceleration and on the
applied force when he formulated his second law is close to near impossible.
Wouldn’t it be wonderful to be able to describe a sports diet in such a way as
to say that increasing your intake of x% of y ingredient will lead to a z%
increase in performance; Alas it is not so. Not only does the diet effect performance
but also a host of other environmental factors that over a prolonged period of
time simply cannot be controlled. In studies of this nature there is a
generalised absence of what would be the control group, for no other reason
than nobody really knows what the control group should actually be. At best we
have “best attempts” to isolate factors and study them but in spite of
tremendous efforts on the part of the researchers they remain in the realm of
bad science simply because of the impossible nature of isolating the parameter
that is being studied or of simply establishing a valid control group, exempt
from being corrupted by other factors. This doesn’t mean their findings are
incorrect, only that they are flawed as a scientific endeavour. It also doesn’t
mean that we haven’t discovered anything; on the contrary, there has been a
major advancement in our knowledge on the topic. But wading our way through the
myriad of scientific complexity is a daunting task, especially when so much
research tends to be contradictory. Translating all of this science into a
practical diet, that is easy to follow and that leads to a genuine optimum
performance for a particular individual is near impossible, especially when we
include the different genotypes of all of the athletes that may be interested
in this material.
What we are left with is a philosophy, a set of general
rules that certainly have a lot of valid use, but are by no means a detailed
recipe for success. Many authors have tried to do just this and as would be
very natural for a topic of this nature they have evoked the theory of
evolution and justified diets on what our bodies had adapted over millions of
years of evolution to eat. Whilst I believe that this approach can successfully
lead to identifying the major trends in an optimum diet, I do not believe that
it can lead to optimum performance in a race. Our ancestors generally had
access to poor quality foods and developed highly efficient systems for
extracting energy from these foods. By injecting high quality, energy rich
foods into this system we can give it an extra boost leading to even greater
performance.
So then, on to the bad science. It is unfortunate,
especially after the introductory paragraphs but the nature of the topic is
such that it is all we have. What I will express is of course is simply an
opinion. I consider it to be a valid opinion though as it is at least coherent
with what I know intellectually and what has worked well for me in running ultra-marathons.
I will argue a case, based on evidence but much in the way that a lawyer would
argue a case in court. I will be coherent in what I say and I will back up with
as much data as I have available. However, it will remain an opinion albeit an
informed one; based on my own academic research as well as my own experience in
running ultramarathons. Ultimately it will be another piece of bad science,
although I will argue there is a lot of truth in what I am offering.
This lack of hard data has been summarised in Mark Hine’s
excellent book “Our natural diet” (http://www.markhines.org/Our-Natural-Diet(2857229).htm)
where Hines draws attention to these very problems and offers an interesting
synopsis of what may well indeed be our natural diet. But is our natural diet
the same as an optimised diet for ultra-endurance running. It is an interesting
question.
The diet for an ultra-endurance athlete has to allow the
athlete to achieve the following goals. First and foremost has to be the
ability to maintain a prolonged effort over a prolonged period of time.
Following that the diet has to provide enough energy for adequate training,
allowing the athlete to achieve his or her goals. Coupled in has to be the
aspect of good health. A sudden burst of energy for training purposed does not
necessarily constitute optimum diet if we are considering our long term health.
Back to the bad science then. In the void of any hard
reliable data upon which to make any hard scientific conclusions the developed
world in general came to the conclusion in the 1980s (http://understandnutrition.com/2013/05/08/the-low-fat-diet-why-it-was-so-popular-and-where-it-stands-today)
that fat was bad. As athletes, weight is one of the most important aspects that
have an effect on performance. Carrying a couple of extra kilos has a huge
effect and slows you down so there is immense interest in keeping that weight
off, or losing it if we carry too much of it. So when the general opinion in
the field was that eating fat made you fat, we all diligently followed our low
fat diets, convinced that this was the only way forwards to optimum performance.
The problem is that this mind set has recently been shown to be complete
nonsense. (http://realmealrevolution.com/)
Noakes is in my opinion one of the very best sport’s scientist ever in the
field. Not only because he has written a host of literature based on actual
research but because he is willing to change his opinion and recognise that he
was wrong with previous conclusions that he had made. His book “The Lore of
running” is the staple reference point for any runner that is seriously
considering a fuller understanding of the science behind the sport.
So then, back to the fat. Our bodies are tremendously
adaptable and we are capable of adaptations in our diet that allows us to
extract the necessary nutrients from our food so that we may go about our
business. When we reduce or even eliminate fat in our diets, in an attempt to
lose weight our bodies adapt to this regime. If the major source of calories is
then carbohydrates our bodies become adapted to processing carbohydrates, and
that includes converting the carbohydrate into fat to make up for the very lack
of fat. The very biochemistry of our bodies changes in order to extract what is
needed. And fat is needed. It is not only needed for fuel but also it plays an
important role in cell protection and hence reduction in the risk for cancer. (http://www.thenaturalvet.net/Fats-and-Their-Relationship-to-Cell-Membrane-Function_ep_61.html)
A host of studies analysing glycogen (Carbohydrate) stores
and performance arrived at the conclusion that at least up until the marathon
distance that the primary fuel for performance was glycogen. In other words
stored carbohydrate and athletes went to great ends to optimise these stores.
These included the low fat high carb diets as well as the famed carbo loading
regimes that athletes undertook the days previous to a race. Carbo stores in
the body can typically last for 2-3 hours which is just the right amount for a
marathon. When the carbs run out, the athletes experience the wall effect with
the subsequent dramatic decrease in work rate.
Studies on triathletes, particularly for the Iron man distance
(http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4445872/)
clearly demonstrated that the top athletes could not be burning carbohydrates
as the major energy source for the duration of the event. They were winning
races in about 8 hours, a supposed full 5 hours over the point when their bodies
ran out of glycogen. Not only that, but at the work rates involved, whatever
mechanism was producing the energy it was just as efficient as the carbohydrate
burning mechanism of the marathon runners and lasted a lot, lot longer. It is
this precisely this latter mechanism that we are interested in in ultra-running
if we are to truly unleash our potential.
So, in the low fat, high carb diet the body is being
constantly trained for precisely that combination and never really learns to
burn fat. The body becomes adapted to carbs as the primary fuel source, so when
the carbs run out, the body subsequently crashes. But it doesn’t crash because
it has run out of fuel, it actually crashes because it doesn’t know how to burn
the huge reserves of fat fuel that it still has. It is little wonder that
whilst on this diet, study after study has demonstrated that it was the amount
of stored glycogen that affected endurance performance and every possible trick
was used to get more carbs into the body. (http://musclesound.com/glycogen-role-in-sports-performance)
Once the carbs ran out, the athlete hit
the wall. The problem was though, that this still didn’t explain the top
performances of the top triathletes as they were able to keep up work rates
comparable to the top marathon runners but clearly they were not hitting the
wall at 3 hours. They weren’t even hitting it 3 hours later. What was
happening? And then came the revelation that shocked the sports science
community: These athletes were not actually following a low fat diet after all and
they were compensating with significant calories from fat. Not only that but
the athletes actually confessed to “cheating” on their trainers prescribed diet
and were eating considerable fat as well. The conclusion being of course that
these athletes were fat adapted. They were not actually using carbs as their
major energy supply but fats; stored body fats. Their bodies were so efficient
at burning fats that they were capable of comparable work rates to the top
marathoners of the day who were burning carbs. So instead of focusing on
improving our ability to store glycogen we should be training our bodies to
burn fats.
So the low fat diet recommended by so many sports nutritionists
would not only appear to be highly mistaken for an ultra-runner but it would
also appear to be a major hindrance in achieving optimum performance. By eating
a low fat, high carb diet, the body becomes adapted to metabolising carbs, and
more importantly it becomes very poor at metabolising fats. What we need to do
is move to a high fat low carb diet in order to train our bodies to burn fat.
When all we have is fat to burn, the body adapts to burning fat, and when the
body is properly fat adapted it can run and run and run for a very long time. And
this is precisely what we are trying to achieve in our ultra-running.
So the high fat diet has suddenly become fashionable and there
is a growing trend in the sport towards it. With the same mistaken evangelism
that promoted the low fat diet, we now seem to be becoming obsessed with the
low carb diet. Carbs, at least to some extent have become demonised and a
dietary backlash against carbs is now being observed. But going completely the
other way isn’t the answer either. Those elite triathletes that were sneaking
fats into their diets and doing the top times in Ironmans weren’t just only
eating fats. They were eating considerable carbohydrates too. More
specifically; carbohydrates were the official staple of their diets but, and it
is an important but; they were eating considerable fat too. In other words, and
this is where we come full circle; they were eating a balanced diet! This of
course actually makes good common sense. Extremes in general are bad and often
the best way is somewhere in the middle.
The “high fat - low carb” paradigm is equally misleading as
the “low fat - high carb” one. Both terms are inherently mistaken and both lead
to considerable imbalances for what can be considered as being optimum
performance in ultra-endurance athletics. What we should be talking about is
simple shifts in the percentages of these nutrients, and subtle shifts at that.
Barry Spears “The zone diet” (https://en.wikipidia.org/wiki/Zone_diet)
does just this and whilst anyone trying to follow this diet will require a
degree in biochemistry to understand what he is going on about, the message can
be neatly summarised as eating a bit more proteins and fats and a bit less
carbs. Instead of eating 60% carbs, Spears recommends approximately 40% carbs
with 30% fat and 30% protein. This can hardly be called a low carb diet as
carbs still make up the greatest proportion of the macro nutrients but it is
never the less an important shift from the more established traditional
marathon runners diet. More to the point, the USA national swimming team that
Spears coached whilst on his diet ran riot in the in 1980s and
took pretty much all the medals that were worth having in the USA. Clearly he was on to
something.
Training the fat metabolism.
The first stage in training our bodies to metabolise fat is
clearly to increase the fat in our diet. (http://www.bodybuilding.com/fun/how-eating-more-fat-helps-you-lose-more-weight.html)
This doesn’t mean eating massive amounts of fat like the famed Atkins diet but
simply shifting the emphasis of the diet towards fats. Remember, we are
adjusting the percentages without making major jumps. 30% of total calories
from fat, on a day to day basis can be considered as a healthy “high fat” diet.
(http://www.mensjournal.com/health-fitness/nutrition/why-experts-now-think-you-should-eat-more-fat-20141020)
But also an important aspect of training fat metabolism is to train when the
body is depleted in carbs. This can best be achieved first thing in the morning
and training before having anything to eat. Whilst the body will not be
completely depleted as the glycogen reserves will not be empty, they will be significantly
depleted and as all food from the previous evening will be digested it will at
least force the body to access the reserves and this includes the fat reserves.
It is important not to force the body too hard straight after waking up,
especially as we get older and lose the elasticity in our arteries but by all
accounts, a lower work rate leads to a higher percentage fat consumption,
although total amount of fat burned increases with exercise intensity. (http://fitnesshealth.co/blogs/fitness/14112669-best-heart-rate-to-burn-fat).
Personally I train religiously every day before work for about an hour. I take
a coffee to get me going and then hit the road no matter what. Consistency and
the formation of the habit are absolutely crucial in provoking the fat
adaptation to take place. It is a slow process and not something that happens
quickly. If you chose this route to ultramarathon success you have to be
prepared to forsake short term gains for the long term ones. Training for
ultra-marathons is even more arduous than the races themselves.
The major component of any ultra-distance athlete’s training
programme has to be the weekly long run. Out of racing season this will
typically be anything between 4 to 6 hours with the occasional 10 hour run for
me. On these runs you have to eat whilst you run and although I have no
scientific evidence or research to back up some of the following statements, I
can say that my own personal experience more than justifies what I am
recommending. We are interested in burning fats, but to burn fats we also need
to burn carbohydrates (http://www.sport-fitness-advisor.com/energysystems.html).
A useful analogy is that of the pilot light and the major flame in a furnace.
Without the pilot light of the carb flame burning, it is impossible to ignite
the major fat flame. To this end it is important to consume carbohydrate during
the long runs as without them, the fat flame does not burn. But the trick and
it is a difficult trick to master is to consume just enough to keep the pilot
burning, thus forcing the major fat flame to keep burning. Too little carbs and
the flame goes out, too much carbs and the body takes the easy way out and
burns them, at the expense of the fat flame.
So just how much carbs should you eat on you long training
runs? There really is only one answer to that as far as fat adaption goes and
that is as little as possible. When you feel your energy beginning to dip then
that is definitely NOT the moment to take the carbs. This of course flies
directly in the face of traditional advice which recommends taking carbs on a
regular basis precisely to avoid this dip. Only when you are starting to feel
light headed and that there is a considerable loss in performance should you
eat them. And they should be relatively difficult carbs to extract as well such
as fruit. Personally I go for the dried fruit as it is energy dense
relative to the weight you have to carry. Gels are absolute no no’s as far as
training runs are concerned. You will take just enough to lift you out of the
downer, and absolutely no more if you are genuinely interested in adapting your
body for fat burning. I am a great fan of dried fruit and nuts. The dried fruit
contains the carbs and the nuts contain lots of fat and proteins. At this point
I need to point out that this is what seems to work for me. This is definitely
not a statement based on a literature research.
In taking this strategy it is very easy to get it wrong. In
a carbohydrate depleted environment you are essentially starving yourself. We
have seen that carbs are important in the fat metabolising process and the
complete absence of them in the body can be catastrophic. Indeed, the body will
simply not allow a complete absence of them in the body and it has been show
(https://en.wikipedia.org/wiki/Gluconeogenesis) that in the absence of glucose in the blood, the body
manufactures glucose by catabolising proteins. The brain mostly functions on glucose
so the very survival of the organism depends on carbs being present in the
system and will not allow zero point to be reached and starts to manufacture them internally. In lay terms that is tantamount to the body eating its own muscles and that
is clearly counterproductive to any sports performance.
Clearly though, the purpose of all this is to promote fat
adaptation and must not be confused with other aspects of training. This
requires some considerable discipline and self-knowledge as this will almost
certainly equate to slower times in the training runs compared to fuelling them
with a carbohydrate rich foods. Indeed, on a typical 50 km training run that I
often do, I will deliberately set out without eating breakfast. On a day with
breakfast this will often take me 4:40 at a reasonable training pace. Without
breakfast it always takes more than 5 hours, sometimes even longer. A casual
observer will immediately point out that you can’t train properly without
having eaten breakfast as you are clearly not working as hard and that the
difference in times proves the point. However, the whole point of training
whilst in a fasted state is not speed per se but is all about developing the
fat adaption. Continuous races that take place over several days are not won on
speed. They are won on endurance, and endurance is all about development of the
fat metabolism mechanism in ultra events.
Other legitimate aims of any training session such as
increasing your aerobic capacity and the development of speed clearly cannot be
achieved by taking this strategy and more carbs should be consumed. Indeed,
when I want to practice race pace, or develop speed I will always eat
breakfast. For speed the body needs to be well fuelled. However, I would argue
that the major purpose of the weekly long run for an ultra-distance athlete is
to promote endurance and fat adaptation. Improvements in aerobic capacity and
pace are the realm of shorter distance higher intensity workouts. The fact that
the training run takes longer should not be the issue here, you are training
for performance on race day and that will require shorter term sacrifices. But
little by little, especially if you start to keep accurate records of your own
training you will notice improvements in speed and endurance as the fat
metabolism starts to become more efficient in your body.
Race day.
On race day we are all looking for a maximum performance. An
ultra-marathon race for me can be easily divided into two sub categories as far
as nutrition is concerned. The first are the 100 k races on tarmac or good
trails. They are fast races and typically take less than 12 hours. My last 100 k
clocked in at 8:49 which is not too shoddy a performance for a 51 year old. More
importantly, my pace was extremely uniform and at no time during the race did I
run out of energy or hit the wall. In this last race I didn’t eat breakfast.
Not because it was part of the race plan but because I simply wasn’t hungry. Hunger
is a good indicator to if we actually need food or not and for an ultra-run, I
am not in favour of forcing the issue. I had a good fatty meal of sausages, ham
and eggs the night before with just a few chips so I knew my reserves were
full. I was also less worried about the absence of breakfast as I know that my
fat burning metabolism is good. During the race, as soon as I noticed even a
slight drop in speed I would drink an energy drink, or take a gel. The purpose
of race day is to perform. Race day is when you get back what you put in and
then, and only then is when you fuel your body for maximum performance and that
means carbs. The train low, compete high strategy has indeed gainded popularity
amongst many elite athletes. (http://awordonnutrition.com/sepost/train-low-compete-high-a-quick-summary/?type=article)
When you have trained properly in a carb depleted
environment you have developed your fat metabolism to the full and when you
finally inject considerable carbs into your body whilst running it is like
igniting it with rocket fuel. The high consumption of carbs during the race not
only keeps the pilot light burning brighter but also allows this very pilot
light to ignite even more fats as though they were being burned in a blast
furnace. What you are doing on race day by taking in high quantities of
concentrated carbohydrate is actually providing an optimised environment for
the burning of fats. And that leads to optimum performance. It is easy to
understand the origins of the mistaken carbohydrate paradigm for optimum sports
performance in ultra-distance athletics; the true function being that carbs
facilitate fat burning. However, the underlying point, and it is one that
cannot be stressed with sufficient force is that this only works in fat adapted
athletes. During training it is a low carb diet; in a race it is high carbs
still.
For any race that takes over 12 hours we require a different
strategy. My own experience on relying on carbs and my internal fat store alone
simply does not seem to cut it. Races over the 100k distance can take anything
between 24 and 72 hours; at least for the kind of races that I like to do and
the fuelling strategy returns to what could only be described as a typical
balanced diet, at least in terms of the macronutrients. I will go for
concentrated foods as in fibre depleted but certainly the combination of
macronutrients resembles a typical food pyramid. After 12 hours I can only
imagine that my fat reserves start to fail too. I clearly have much more fat to
metabolise, I can see it; but after 12 hours it certainly appears that all of
the readily available fat seems to have been burned and that accessing that
second store of fat requires a bit more work.
The pace that the longer runs are run at is quite a bit
slower than a typical 100k and that means that eating solid food is not only
feasible but is actually quite pleasant as well. The intake of solid food early
on in the race, and by that I mean a good combination of carbs, fats and
proteins seems to keep me going for a very long time indeed.
A particular revelation in my own experience took place when
I was running the Badwater ultra marathon in the States. About the half way
point I switched to eating sandwiches that were soaked in olive oil and that
seemed to pick me up and give me a massive boost of sustainable energy, far
above the energy levels that I was experiencing by eating carbs alone. The
combination of the carbs, and I strongly suspect the oil, provided a huge amount
of fuel that went straight into the furnace. So, is it possible that we run out
of available fat reserves too? And by replenishing these with readily
digestible fats like olive oil we substitute the readily available fats in our
bodies? The fat burning mechanisms in our body are already fully activated and
all they need are the fats to burn. This would indeed be a great topic for a
scientific study but in the absence of which I will simply try to perfect the
method empirically on my own experience. Eating fats after 12 hours into the
race it would certainly appear; equates to optimum endurance performance in the
longer events.
Summary.
Summarising then, fat is the major energy provider during an
ultra-endurance event and as such athletes should be training in such a way as
to promote this biochemical pathway in the body and this means training in a
carb depleted state, typically fasted and before breakfast.
As a general rule, an ultra-endurance athlete should be
eating a balanced healthy diet but one that is subtly shifted towards fats,
with no radical exclusion of carbs. Carbs are still very important.
During a race the athlete needs to consume more carbohydrates
than in training in order to reach optimum performance and the longer the race,
the more important are the fats and these have to be consumed to maintain performance.
And finally, before I get slated for the “bad
science” this is just a synopsis of my experience and stuff I have read. I’ll
leave it up to the actual sports scientists to collect the data
and verify the hypothesis.