The Marathon des Sables

There have been some comments on the complete lack of calories I am taking and it’s true, there really isn’t a lot. But this is OK, we can dip into some of the amazing mechanisms that evolution has provided us with, and in this instance it’s body fat reserves.

If you have 15% body fat (’average’ for a male) you have enough energy stored in your body to run at marathon pace for 3 days straight … everything else would give up long before you ran out of energy! This energy store was of course to help people when times were lean.

So, how do I work out what I need?

Firstly I worked out my Basal Metabolic Rate using the Harris-Benedict Equation, using the heavy excercise factor I my BMR is normally

3394 = 1.752 * (66+(6.23*180)+(12.7*73)-(6.8*26))

For the purposes of this I am going to use the average factor (moderate excercise) and add the estimated use on, the BMR is now a nearly average
3003.

Lets add the excercise on to that. Running on the road with no pack burns approx’ 1cal/kg/km. So, 1*82kg*250kg = 20500 cals for the weeks running effort, lets conservatively add 40% to that to account for sand/backpack/hills, thats 28700cals for the running. Lets add the daily BMR for the 7 days (7*3003), 21021, so total calorie consumption is 49721.

So I need to find approx’ a whopping 33000 calories from me…

In terms of energy stored body fat holds around 3500 per lb, which means I need at least 9.2lbs of body fat to serve my needs during the race. 9.2lb = 4.2kgs. 4.2kg is about 5% of my body mass. So provided I have the base level of around 4% & and extra 5% body fat I should be fine.

Realistically, total energy consumption could be even higher so here is hoping I have at least 9% body fat, because although there will likely be a little bit, muscle catabolism is painful and inefficient!

Isn’t the human body amazing?

I have today ordered my food (finally, I hear you say!) from be-well.co.uk. They came up with a programme for me after a chat over the phone.
Be-well manufacture freeze dried foods and related products, the list of althetes they supply is very impressive.

The final food programme I have gives approx 2360cals/day and each day consists of the following:

• 2 * Breakfasts @ 1395 calories
• 1 * Main Meal @ 450-550 calories
• 1 * Pudding @ 450 calories
• 1 * Recovery Drink
• 1 * Flapjack

To add to the breakfast I will use a Chocolate Honey Stinger gel to sweeten it up (as I have opted out of having the fruit in there) but this is optional and I could have it later on.

In addition I am planning on taking some SIS Go powder sachets and powerbar blackcurrent caffeine gels. Be-well do a range of drinks which I will try out at somepoint, unfortunatley I feel it’s too late to switch to something new.

All in all, if you are planning on an expedition then these guys are worth chatting too. I will of course report on how it all was after the big event, which is suprisingly close …

Now I have had a chance to ‘road’ test my Aarn pack on last Saturdays Grantham run I thought I would put a few words up about the about it the features that really stood out and make the pack great.

The first is the weight and general construction, it feels lightweight to hold and the construction feels strong … standard boring points but crucial non the less.
When full, the claim it doesn’t round out are well founded and stuffed with cusions (scientific, eh!) the back stays flush with your back so the pressure to specific parts of your back are not increased when full like with some packs.

The next part of the system that I really like is the adjustable clip system between the shoulder straps and the main body of the pack. One advantage of this is that any wobble (and I found this to be very minimal) is not transferred to the shoulder straps so they stay still.

The mesh on the back distributes any pressure well over the whole of your back, its super squishy construction moulds to your back. I didn’t get too sweaty on the run and my guess is it does a good job of venting but a February run will never test that!

One question that has been pondered is the best way to attach a sleeping mat. I have plumped for the Z-Lite by Thermarest and will be cutting 5 panels off.
I ran with it strapped horizontally, using the ice axe straps and the hood clip to strap the mat too. Having looked at a couple of options I have decided I favour the method pictured below. With one strap it’s very secure.

The range of moment the pack gives you is great too and tops of what is a very comfy pack.

It’s a big mileage bonanza this week, I’m having a fairly large mileage week this week, it should be around 91 miles at the very minimum. It’s not too easy to fit it in with the usual bustles of weekly life but it does feel good to do it. So far it’s been mostly on the road (28 with a pack) and I must say … I feel good!

To make it better a few us “MdS class of ‘09″ are meeting up for a couple of nights and a couple of training runs in the glorious town of Pontypridd, Wales. The honorary member of the crew, Andy, has done the route finding and the organisation. I take my hat off to you, sir!

I have been busy of late with kit choice and bar glueing on my gaiters I am almost good to go, courtesy of Dan the backpack is on its way over from Oz.

It’s all getting very exiting!

I am not ashamed to say that I like my expedition foods, but being the greedy oik that I am I could do with a little more packing, just a soupçon more if you would (well OK, quite a bit more).
So after a little experimentation I have managed to boost them up nicely, to a whopping 1350cals each.

These noodles retail at a whole 33p each from J Sainsburies… they make up a rather fine 550 cals/85g of dried weight.

1. Make your expedition food (I tried spag’ bol), to the recommended line and stir & close.
2. Go wild and crush up your noodles.
3. Open said noodles.
4. Throw away the seasoning sachet (or not if you like), you will loose some calories if you do but it’s marginal.
5. Open the meal up, chuck ‘em in your expedition meal, add water back up to specified line with water.
6. Close.
7. Leave for the prescribed time.
8. Open.
9. Stuff yourself silly.

The noodles pack out nicely without distracting from the gourmet delights as intended and add the whopping number of calories, they are also, of course, optional should you not want to do it now and just fancy a snack later one.