Tuesday, June 14, 2016

Food and drink

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 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.    

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