The Marathon Des Sables (MdS) is known as the toughest footrace on Earth. The distance covered is 243km's in the Sahara desert, run in 49 degrees Celsius heat while every athlete carries his or her own equipment, food etc. weighing in at around 9-13kg's.
This blog is aimed at telling my story. I will record my preparation for the MdS 2013 in detail in the hope that it will help my fellow runners.
My training is coming along just fine.I will be doing 86km's this week and 95km's next week. Getting both stronger and faster running with 7kg's of weight on my back. I will have to get to the UK to speak to Rory Coleman, who has done eight Marathon des Sables, about how to keep the race pack weight down.
Below is a photo of my 10km run with 7kg's in 28 degrees Celsius today.
10km's with 7kg's on my back in 57 min and 25 seconds is an average time of 5:45 per kilometer or an average speed of 10.43 km/h.
Tomorrow is 30km's with 7kg's of weight and 2 weeks from tomorrow is a 100km three day training run. It will be a great opportunity to expand my nutrition experiment. I will keep everyone up to date by publishing some details on this blog.
I have also received my new Kestrel Talon TT custom carbon triathlon bike with which I will be doing the IronMan 70.3 in January 2013 as strength training for the MdS.
I decided at the start of this week to take it easy. I left
the weight at home and ran for the fun of it. Without the weight on my back I
felt naked and initially a little guilty but the pleasure of running for the
fun of it soon wiped away all guilt.
The result was a 52:02, 10km on Monday. I still ran a total
of 60km’s this week and added a 10km bike ride. In the future I will add more
cycling kilometres as part of my cross training. I also received the race pack
I ordered from RaceKit, a Runner R-Light 30L with the Equilibre R-Light front
pack. I will be testing it out in the week to come.
Overall it has been a week of running for the fun of it. I
also spent a great deal of time researching nutrition and will shortly share
what I have found, as well as my personal experience in testing some of the
ideas and theories. Hopefully it will be of benefit to some of you as well.
Congratulations to my wife who ran her first 10km today.
Having logged around 600km’s
since early January 2012 in my Nike Structure 14’s, I decided it’s time to get
a new pair of running shoes. In the spirit of experimentation I set out on
Saturday morning with some expectation to the local sport megastore close to my
home.
Two things to note, though: (1)
My Structure 14’s are by no means run-out, but the off road running on my long
run is becoming more and more uncomfortable, indicating to me that it might be
best, in the interest of avoiding injuries to get a new pair of running shoes.
(2) I will continue to use my Structure 14’s on my daily 10km runs, as this is
predominantly on a tar surface, for at least the next 6-weeks, before retiring
them to casual ware around the house. This is of course subject to me being
able to convince my wife that the shoes are suited for casual wear. I recall
her statement that the colour of my Structure 14’s was not suited for public
wear. In fairness my Structure 14’s are a very intense shade of blue, so my
wife may have a point.
But I digress, so let me return
to the acquisition of shoes. The selection available at Sportsman Warehouse was
impressive. A running circuit in that shop provides a suitable environment for
testing before buying, and the staff members have a decent knowledge of the
products on offer.
I decided to review a number of
shoes that had found their place on my shortlist. My criteria for a running
shoe are obviously directed at finding a shoe that I can continue to use
throughout my training, and at the Marathon des Sables event. It has to be a
strong shoe, capable of handling the environment, sand, excessive heat,
freezing temperatures at night, stones, have good traction for the areas where
we cross uneven terrain, be light, but most of all fit well enough to prevent
blistering, while being able to absorb the continuous pounding of high mileage.
Weeks of reading reviews produced
a shortlist of the following shoes, which would suite my specific running style
and foot preference. I generally go for a neutral shoe with good absorption or
rather cushioning properties, to use the correct running term.
Short List
The following shoes were on my
shortlist. I spent a great deal of time assessing each shoe against my own
personal criteria. This included elements of weight, how well the shoe is
constructed, and its ability to breathe while still able to keep sand and
stones out, and its ability to cushion running impact, which is a real priority
for me. These elements formed the basis of my own criteria, and many of my
readers will have very different thoughts and ideas on what is appropriate for
them.
However, I do believe that the
reviews and links provided has some merit and will provide some food for
thought.
My eventual choice was the Nike Alvord 9 trail running shoe.
Alvord 9 Running
Experience
I took my new Nike Air Alvord 9’s
for their first 10km run on Monday. The experience was pleasant with the shoe
providing much needed cushioning even with the added 7,5kg’s of my race pack.
At an average speed of 9,5km’s/h with around 25% off-road the shoe was
comfortable, absorbing running impact efficiently. On the off-road sections the
shoe had adequate traction with excellent breathability even at 31 degrees
Celsius. In general one of the best shoes I have had the pleasure running in,
in recent months.
The shoe might not be suited to a
desert race such as the Marathon des Sables. I am not convinced that it will in
its present design keep sand out. It might be that gaiters glued to the side of
the soles might solve this problem. I will most definitely test this in the
future and provide some feedback. The truth is that I was so impressed with
this shoe that I returned on Tuesday to buy four pairs for me, and a pair for
my wife. My five pairs should give me around 3,000km’s of use at around 600km’s
each. I know that this is around 60% of what I can expect to get out of my shoes;
however, my previous heel injury has made me a little paranoid so I try to
change shoes before the cushioning starts to diminish. So with my reserves
stacked in my cupboard I should be good until the middle of August this year.
Future Shoes to Test
There are, however, dedicated
desert running shoes that I will consider testing in months to come. These
shoes have been tried and tested within a desert environment, and one
specifically within the Marathon des Sables.
Lookout for my review on the
following shoes in the future:
UK Gear PT-03 Sandproof Desert/Hot Environment Running Shoes
This shoe has apparently been
designed for an extreme heat environment, is durable with excellent cushioning.
It is claimed to be sandproof when used with Gaitors. It is the approved US
Army Running shoe and has been tested in Afghanistan and Iraq. The manufacturer
claims that this shoe is in use in the following armed forces: Germany since 2004,
British since 2004, US Air Force Academy since 2007, US Military Academy West
Point since 2008, Polish Special Forces since 2008, and the Gurkhas since 2006.
And to top it all this shoes apparently weigh only 385 grams. It also has
spousal approval, with my wife thinking that it will look cool with some jeans.
I do insist, however, that I will not be running the MdS with jeans.
New Balance 1100
The New Balance 1100 or M1100MDS
is the official shoe of the Marathon des Sables. It weighs in at 388 grams, incorporates
a microscopic velcro-closure gaiter to keep the sand out and has been tried and
tested in the most extreme of environments. My impression is that this might be
the ultimate MdS shoe. My wife, however, gave it a run only status. On her
rating scale this shoe is not cool and she can’s stress it hard enough that I
will not be wearing these with my jeans before, during or afterwards. In short,
it might be a brilliant shoe for the MdS, but it has my wife’s fullest disapproval
for casual wear.
Teva Desert Shield
The Teva’s Desert Shield was
custom made for Teva’s sponsored athletes. Beyond this I know very little about
the shoe, but will definitely do some homework to get on top of a shoe that
might have a much wider application than just the MdS desert race.
My final shoes to examine are the
shoes on offer by Salomon, which are also claimed to have been made with the
MdS in mind.
Please note that my comments
below are my present understanding of the various processes that come into play
and are not claimed to be absolutely accurate or authorative. It is an
experiment and I am reflecting my thoughts about the issue here. I am also
experimenting with various refueling strategies in this entry and am providing
my rational for these. I will most likely adapt these over time as I gain a
better understanding of the process, am able to access additional research and
test the various strategies, eating plans and ideas. I will continue to update
my eating strategy so revisit this blog from time to time.
Your comments are
welcome!
I am at the stage in my training that
I feel the decline in performance during my long run. If I split the distance
into two, running each at different times during the same 12 hour period my
performance is maintained. This I ascribe, after some research, to basic
running physiology, which simply means that my energy stores become somewhat depleted
during my long run.
Example of my weekly training:
Mon: 10km @ 10km/h pace with 6.5kg weight,
Tue: 7km @ 8.2km/h pace with 6.5kg weight,
Wed: 10km @ 10km/h pace with 6.5kg weight,
Thu: 7km @ 8.2km/h pace with 6.5kg weight,
Fri: 26km @ 8.35km/h pace with 6.5kg weight,
Sat: REST,
Sun: 7km @ 8.2km/h pace with 6.5kg weight,
The truth is I have done this
intentionally. I decided to use the MdS preparation to challenge my own
previous knowledge, to experiment again and to find those elements in training,
nutrition and strategy that really work.
I therefore went back to the
present research to understand the physiological process at work during my
running and in specific my long run. My understanding of this process is the
following:
When
we ingest ‘food’ it is broken down into sugars which are absorbed into our
bloodstream in the form of glucose,
The
hormone Insulin is released by our pancreas and moves the sugar from the
bloodstream into cells where it is used as a source of energy,
The
glucose serves as an immediate source of energy,
If
there is excess glucose (more than what the cells need as an energy source) it
is stored in the liver and muscle tissue as glycogen,
If
during a period of activity, the energy source (glucose) in the bloodstream falls
below a pre-determined level, the glycogen is released back into the
bloodstream for use, and
If
all energy needs are met, the excess glycogen is stored as fat.
The primary questions, therefore,
are how much glucose reserves are readily available at any given time, and how
much energy will I consume during a specific activity. The aim of answering
these two questions is to establish a strategy through which to ensure that
energy reserves are easily available for use.
How much glucose reserves are readily available at any given time?
The research seems to indicate
that the body is allowed to burn the easily accessible energy reserves
(glucose) in the bloodstream up to a depletion point of around 50%. At this
point the body switches over to burning fat reserves as a source of energy. For
most runners this depletion point is reached at around the 30km mark (or
somewhere between 2 ½ and 3 ½ hours). As an average we will work on a 3 hour
timeline. Sport nutritionists, therefore, recommend a carbohydrate intake every
45 minutes, which translates to less than 12.5% blood glucose depletion.
Through constant replenishment, the reserve does not get depleted and exercise
can be sustained indefinitely (in theory).
It is noted that there is a fair
level of consensus that weather plays an important role. In warmer weather
energy usage is accelerated, which means that refueling should happen more
regularly. The suggestion is that during normal conditions refueling should
take place every 30 minutes, and during warmer weather more frequently.
There is also the issue of how
long it takes from the point of ingestion until the energy reserve is available
in the bloodstream. The recommendation that a carbohydrate rich meal is to be
ingested 2 to 4 hours before the race may hold the answer.
The following is a rough guide to
the time it takes various food types to become available in the bloodstream as
an energy source after ingestion:
Food
Type
Digestion
Rate
Sugar (Sweets)
Immediate
Fruits
Immediate
Carbohydrates
1 to 2 hours
Proteins
4 hours
Fat
6 to 8 hours
This conversion timeline together
with research done in the 1960’s and 70’s gave rise to the commonly held belief
that ‘carbohydrate loading’ is the most beneficial means of replenishing and
maintaining energy levels during exercise.
It seems obvious that a carbohydrate rich meal 2 to 4 hours prior to
exercise ensures that energy reserves are at optimal level from the start. With
this strategy, maintenance is vital in the sense that an attempt must be made
to maintain the blood glucose level at an optimal (undepleted) level.
It is furthermore worthwhile to
note that every gram of protein and carbohydrate contains in the region of 16.7
kilojoules, and a gram of fat contains 37.7 kilojoules. Looking back at my most
recent training log, it seems as if I consume about 100 calories per kilometre
or put another way, around 884 calories per hour, based upon my average overall
run time of 8,84km/h. This rate of energy consumption is not standard and
differs based upon gender, age, weight and running speed, so has to be specifically
calculated.
For me, however, starting from an
optimal, fully fuelled, position I will burn about 1761kJ within the first 30
minutes of my run (842/2 x 4.184), and continue to do so throughout. My aim
should therefore be to consume 1761kJ per 30 minutes or in my case every 4.3
km’s. As sugars are immediate it might cause a spike in glucose levels with
possible complications of its own, proteins and fats may take too long to enter
the bloodstream. At first glance this seems to point towards carbohydrates as
the food source of choice.
One option proposed is to stock
up two to four hours before the run with 400 to 800 carbohydrate calories, and
to refuel during the run by taking in 200ml water per 20 minutes, and about 100
calories every 30 minutes (Bean 2006). This plan means that I would start the
race with around 3280kJ of energy available from the outset. I would,
furthermore, add to this an additional 418kJ of energy every 30 minutes. My energy
input during a 3 hour run (at 8.6km/h - 26km’s) would come to 5788kJ’s while my
energy output would be in the order of 10350kJ’s. The energy shortfall of
4562kJ’s (1090 calories) must be extracted from existing blood sugar levels,
liver and fat stores.
Here is the strategy I used for my
experimental run:
I
ate 800 carbohydrate calories 2 hours before my run,
I
took 2,0 liters of water on the run to consume over the entire period, and
I
consumed a GU energy gel at the start, and one after every 30 minutes of the
run.
My Personal Experience:
My use and review of these
supplements has to be understood within the context of my present diet. In
September 2011 I decided to change my diet to the following:
(1)No
starches,
(2)No
sugar,
(3)High
Protein, and
(4)Water
only.
I effectively cut carbohydrates
and sugars from my diet. At the same time I started to exercise, building my
routine up slowly from inactivity (due to a previous injury that resulted in an
inactive lifestyle for close to two years), to its present level of 67km’s (38
miles) per week with added weight. During this time I lost 23kg’s, and although
I removed both carbohydrates and sugar from my diet had no excessive fatigue or
noticeable drawbacks. I recover quickly after a run, am injury free for the most
part, and continue to increase my exercise intensity.
My blood pressure is normal at 120/79,
resting heart rate is 55bpm and my maximum heart rate increases to 165 bpm at a
2:40/km pace. A recent ECG provided no indication of any underlying cardiac
problems, cholesterol is normal and in general I am healthy although my diet is
limited to high protein such as, eggs, fish, nuts, and red-meat (±
350 to 400g per day in total) and around 2-3 litres of water.
I don’t eat breakfast but eat
between 30 and 60g of nuts at 10:00am, some dried meat (30 to 60g) at around
12:00 and a dinner that is on occasion made more interesting by adding a
tomato, some lettuce or mushrooms. (It is in reality more tasty and interesting
than it sounds). Effectively I consume a maximum of 2000kJ’s per day between
the time that I get up in the morning until I go for my run. It is obvious that
the majority of my running energy does not come from my energy intake but from
fat reserves, resulting in my intentional weight loss.
It is clear that once my weight
reaches my target of 78kg’s (I am at 82.5kg’s at present) that I will have to
increase my energy input to ensure that sufficient reserves are available to
sustain my activity. It is for this reason that I decided to experiment with
gel based energy sources.
Product
I used the GU Energy Gels which are
made up out of carbohydrates and electrolytes. The idea of a carbohydrate
energy source is in line with the present focus on carbo-loading that is
suggested by the majority of sport nutritionists. It made sense to me that
carbohydrates as a source of energy can be timed, is well researched and,
according to conventional knowledge, is the energy source of choice.
It is worthwhile noting that not
all nutritionists agree with this, but I discuss this further on.
Taste
I tried three different flavours,
Chocolate, Lime, and Strawberry. The taste was generally pleasant although very
intense. I had my wife taste the same flavors, her experience was much the
same but she described the taste as less intense. I ascribe this intensity
difference to the fact that I have excluded sugar from my diet for the past six
months. The intensity level of the sweetness of the product dominated the taste
in my mouth. It took me more than 5 minutes to get the first gel down.
During my run I consumed each
sachet in about 30 to 40 seconds at the 30 minute intervals. The taste was so
intense that I felt nauseas. Again, I think this had less to do with the
product and more to do with the sudden dietary change I was inflicting on my
body.
Effect
I experienced no noticeable
effect after taking the gel supplements throughout my long run. I still had, as
before, a difficult patch at between 17 & 18 km’s (which always seems to be
on the same uphill) and ended feeling much the same. My recovery afterwards is
no better. Again, I believe this has more to do with me than with the product.
The gel felt heavy in my stomach, resulted in slime in my mouth and generally
made me feel nauseas.
I think that I might have
stumbled upon an explanation for this in an article published in the IronMan
South Africa magazine (Greenfield 2012). I extracted the relevant statement:
“Most triathlons are relatively
aerobic sports, and many training sessions and longer races do not necessarily
use sugar and starch as primary fuels, but rather rely on fatty acids. From a
biological perspective, this makes sense, since carbohydrates can be rapidly
depleted, and the body can only store a few thousand calories from
carbohydrates, but tens of thousands of calories from fat”.
“If an athlete is eating
primarily pasta, bread, white rice, soy, processed meat substitutes,
non-organic eggs and dairy, and drink a lot of fruit juice, not only could they
be consuming excessive and unnecessary carbohydrate that they are not actually
burning for their sport, but they may also be running the risk of developing
deficiencies in essential fatty acids, amino acids, vitamin D, iron, B12 and
minerals”.
“Nora Gedgaudas, a certified
nutritional therapist and author of Primal Body, Primal Mind, explains it this
way: Fat, in the form of ketones (broken-down fatty acid by products) and free
fatty acids, is the preferred aerobic fuel for the heart and other muscles, and
ketogenic adaptation provides a more steady release of even-burning and
sustainable fuel. It can take a good three or four weeks to adapt to a
fat-based metabolism, following which performance has been shown to be
superior.”
“Nora explains that you get good
at burning fat by depending on fat in the absence of carbohydrates, not by
constantly depending on and burning sugar for fuel”.
My protein based diet translates
into a fatty acid diet. Over the past six months my body has become efficient
in burning fat. It has lost, to a great
extent, its ability to process
carbohydrates and sugar quickly and efficiently, which means that the gel
supplement uptake in my body was inefficient. This has nothing to do with the
product and everything to do with my body.
There are a great number of
performance athletes who find great benefit in using these same gels.
Alternative Views
There is also mounting research
that discards the idea of carbohydrates as a beneficial source of energy. The
following links will provide some interesting information:
The following authors also
provide some interesting reading and research: Gary Taubes, Mark Sission, Dr
Westman, Pierre Dukan, Loren Cordain.
Conclusion
My conclusion is that energy
supplement gels did not work for me; however, there is no evidence to suggest
that it won’t work for other runners. My personal physiology indicates that I
should maintain my intake of protein and fats. This means that consumption
timing is of the essence if I am to ensure a constant performance during an
ultra-event.
Future Strategy
My focus will now shift towards
refining my present diet, and not necessarily changing it. Keeping in mind that
every gram of protein contains 16.7 kilojoules, and one gram of fat contains
37.7 kilojoules, I have a need based drive from which to devise a simplified
and sustainable strategy.
For example, as calculated
earlier, I need around 1761kJ per 30 minutes. This can be provided through the
consumption of dried beef consisting of 30% fat. Such a 30/70 fat to protein
ratio delivers 23kJ’s per gram translating into a requirement of 77g per 30
minutes. A 24 hour 100 miler will require 3,7kg of dried meat. This is just a
crude example and is in need of a balanced composition refinement.
Over the next few months I will
refine my food energy source diet, test this in late July 2012 when I run the
Washie 100 mile race, after which I will report back.
Thank you for visiting my blog,
please come again.
Genis
________________________________
Sources:
Note: 1 Nutritional Calorie is
equal to 4.1868 kilojoules of energy.
Greenfield, B. 2012. IronMan
South Africa. 70.3 Edition. 2012 Spec-Savers. Page 102-106.
