I’ll be
the first to admit my ‘fuelling strategy’ for long walks is awful.
I know (roughly) what I should be
doing, but I never actually do it.
After spending many months
training to get into the best condition possible it can so easily be undone by
incorrectly, or inadequately, keeping the fuel tanks topped up.
I’m normally pretty good to Peel
but then it goes downhill from there.
I’m self sufficient through to
Rushen and I usually take something from each aid station along the way (Banana
or energy/cereal bar (I avoid Mars bars though)), as well as a full refill of
my water bottle at Santon.
One of the big lessons I learnt
in my first long walk (end to end 2010) was to wear a water bottle belt rather
than carrying a bottle in my hand. I lost count of the number of times I
dropped it as my hands were swinging back and forth and either the bottle, or
my thumb, would catch on my trouser pocket.
Yes... trouser pocket.... that
was the second lesson.
Even though they were lightweight
‘hiking’ trousers they were not very comfortable after about 20 miles when the
fabric started to rub on my knee with each step. It’s been shorts ever
since, no matter what the weather is doing.
I have tried the ‘hand grip’ bottle but I don’t like them. It’s much nicer to be ‘hands free’.
One of the other advantages of a
water belt is they usually come with a pocket or two which is very useful for
stashing a few extras such as gels, cereal bar, energy tablets etc.
My usual sports drink is powder
based so on Parish day I will have a small container in my belt containing
enough powder for 1 drink, and I just throw that into my water bottle as part
of my Santon refill.
My support arrives somewhere
between Ballakillowey and the Sloc where I will either get another full sports
drink refill or just plain water, and I will also take half a sandwich. I
try to repeat this every 30-45 minutes through to Peel.
After Peel I find it a real
struggle to eat. While I am drinking plenty and I don’t feel dehydrated
everything I eat is like the cream cracker challenge.
As a result I end up falling back
onto gels and soup which are easy to get down, but can get a bit sickly after a while.
Anyway, I am certainly no expert
in this area, but based on what I have picked up on ‘Tinterweb’ and experienced
through training and races here is my approach.
I work on the basis that I burn
an average of 100 calories per mile at a steady parish pace, which isn’t far
off the figures you see on numerous websites and also matches my Garmin too.
If I am averaging 4.8 mph (12:30
per mile) then I am burning through 480 calories per hour.
In theory I just need to consume
480 calories per hour to even out. However, from what I have read, there
is a limit to how many calories per hour you can actually ‘absorb’, which is
around 300, so already I am 180 calories per hour down.
What you are actually trying to
do here is preserve your glycogen stores in the muscles and the liver for
as long as possible by constantly topping them up, as once they run out you hit the wall. The only fuel
source your brain uses is glycogen so ‘hitting the wall’ is a self preservation
mechanism and just shuts down your muscles, hence it feels like an elephant has
just jumped on your back.
It is possible to recover from
hitting the wall. You just need to slow down (your legs won’t give you
much choice in the matter anyway) and consume some easily digested and quickly
absorbed food/drink (gels/sports drinks are best here), and just keep at a
slower pace while your glycogen stores are slowly restored. It's not a quick process and may take an hour or more before it starts to feel a bit easier again.
‘Carb loading’ is basically
ensuring your glycogen stores are topped up before you start.
The faster you walk, the more
glycogen goes into the ‘chemical reaction’ that powers your muscles.
Even
the slowest of walks will result in glycogen being used, but just less of it so you can
go for longer.
The other ‘fuel’ added to the
chemical reaction is fat, and on the slower paced walks you will use a higher percentage of fat vs glycogen. This means some of the “100 calories per hour” that you are burning
is coming from fat rather than glycogen.
I don’t know what the split is,
but to keep it simple let’s say 50%, so 50 calories are coming from glycogen
and 50 from fat. So, our ‘480 calories per hour’ is now actually 240 per
hour from glycogen (which we want to preserve and keep topped up as much as we
can), and 240 from fat which we don’t need to top up.
Consuming 240 calories per hour,
every hour, for up to 24 hours, now seems much more achievable and a lot easier
on the stomach than 480. That said, I will still try and consume up to
300 per hour (due to the limit you already have on absorbing calories anyway).
A typical energy gel is around
100 calories so you can see why they recommend ‘3 per hour, or less if also
using a sports drink’, as anything more won’t help.
Now you just need to choose the food/drink that works for you and can deliver
those 300 calories per hour, but you need to choose wisely.
Food can be broken down into 3 main categories:
Fats
Proteins
Carbohydrates
Fats take the longest to absorb,
followed by Protein and finally carbs which are digested and absorbed the
quickest.
I therefore avoid eating anything that is high in fat or protein. I don’t
eliminate it altogether, so for example a chicken/tuna mayo sandwich works fine
for me, as do crisps and nuts (although eating these raises the cream cracker challenge
to a whole new level), but I just avoid things like cheese, even if it does go
well with a cream cracker...
Since fats and proteins take the longest to digest and absorb it also means
they are sloshing around in the stomach for a long time which can start to make
you feel bloated and sick.
So, my 300 calories will
primarily come from carbs which opens a whole new topic of what carbs to
consume.
The ‘GI’ rating (Glycemic Index)
can help here.
Foods with a low GI (e.g. nuts,
peanut butter, brown bread) will release their energy more slowly (maybe too
slowly) and also avoid a “sugar rush” which is good, but the downside is they
can end up sitting in the stomach for a long time and give you the bloated/sick
feeling.
Foods with a high GI (e.g.
banana, melon, raisins, white bread, crisps, potatoes) will digest easier and therefore 'release' their calories faster, but can give you a sugar rush.
The other nutrients in a high GI food can slow down the absorbtion, so for
example a Mars bar is quite high GI but is also high fat too and therefore
slows the absorbtion rate down, whereas Kendal mint cake is high GI (100%
sugar) so would give you a bigger rush.
Basically whenever I am out
shopping for goodies I just check the nutritional info looking for something
that can deliver a reasonable amount of calories in a small enough portion to
be eaten easily while walking.
I pay particular attention to the
fat and protein levels per 100g/serving and make sure they are low, and I pay
particular attention to how much of the total carbs are made up from sugar.
The higher the sugar, the higher the GI and the faster they will be
absorbed but also the more chance of a sugar rush.
I tend to go with things that
have at least 50% of their carbs coming from sugar.
If you look at the info for
Kendal mint cake for example, these have 0g fat and 0g protein (good) but you
will normally see 100% of the carbs are made up of sugar. If you can
tolerate this then it’s brilliant stuff, but not everyone can.
A Jaffa cake on the other hand
packs a decent 45 calories per cake, is low in fat and protein, contains 8.6g
of carbs of which 6.4g are sugar (75%), so these are a good choice as they are
also easy to eat, light on the stomach and tasty too.
2 Jaffa cakes every 20 minutes gives
you pretty much your hourly needs.
Soup is a popular choice, but try to go with something that has some decent calories in it rather than a thin watery type. If you aren't up to making your own then my tinned soup of choice is Baxters Chicken and Sweetcorn chowder. It has just under 300 calories per tin and a pretty good 38g of carbs, although only 10g from sugars so is a slower burner.
It also contains some much needed salt too, and there is something comforting about having some hot food, especially as the night draws in. Just heat the soup up at home and keep it in a flask, and bring along some plastic disposable cups.
Just be careful not to make it too hot though. What might feel ok to eat/drink when you prepare it at home will feel significantly hotter to you after you have been walking a while.
I like to have a flask of coffee too. I don't normally take sugar in coffee but I do in the Parish.
Another popular one is mashed potato and gravy. I have never tried that one myself as I haven't quite figured out the practicalities of it but I'm guessing the mash is premade at home so is now cold after being sat in the car, but then some warm (see note above!) gravy is added to warm it up a little. I guess the gravy could be premade in a flask, or made on the fly with bisto granules and a flask of warm water.
I guess instant mash/smash could be used....
At the end of the day everyone is different, and what works for me may not work for you. If chomping down on a full roast chicken which has been stuffed with a block of cheese works for you then go for it.
The only thing I would say is to
avoid anything totally new.
No comments:
Post a Comment