Monday, 15 October 2012

inspiration, maths and rehab !!!

I love it when a plan comes to fruition.  In this case though it's not my plan but that of Felix Baumgartner.  Many years of planning and training went into his achievement earlier this week which I suppose could be described as 'ultra skydiving'.

In case you haven't seen any news recently here's what happened.  Felix went up in a balloon to an altitude of 128, 100 feet (over 39 km).  He then stepped out of the capsule and fell back to earth.  Simple ... or not. Read this on the BBC news website

The videos here and here are truly remarkable and, I'm sure, inspirational to many people.  ME INCLUDED - DEFINITELY.

OK .. now a couple of questions ... how many calories do you burn for every mile (or km) you run ?  And does it matter how fast you run ?

For the mathematicians among us Graydon Snider has worked out that we burn approximately 1 kcal per kg bodyweight for every kilometre we run.  And it doesn't matter how quickly we run either.  The interesting stuff is on his blog.

Which means that in Poland, six weeks ago, my output was:

0.97 x 57.4 x 231.339 = 12880 kcal

[actually it was probably a bit less because my weight fell slightly as the race progressed]

That works out at well over 500 kcal per hour.  My input was just over 315 kcal per hour.

If we rearrange that formula we can decide how far I can run before beginning to get into 'fuel debt'

kcal burned per km  x  my weight  x  distance travelled  =  input during race
0.97 x 57.4 x distance travelled = 7625
therefore distance travelled = 7625 / (0.97 x 57.4)
distance travelled = 136.948 km

It took me about thirteen hours to run that distance.  So, for the final 11 hours my body was in a state of 'fuel debt'.  I was using more that I could take on board.

Another thing to note is that my calorific deficit for the race was

12880 - 7625 = 5255 kcal

To get that fuel my body burned some of it's stored reserves.  One gram of carbohydrates has about 4 kcal, one gram of protein also has about 4 kcal, one gram of fat has about 9 kcal.

If my body used stored carbs, that would weigh 5255 / 4 = 1.314 kg
if my body used stored protein, that would also be 1.314 kg
but if my body used stored fat, that would weigh 5255 / 9  = 0.584 kg

In truth I used a mixture of the three but the point is that, in theory at least, if I started with a weight of 57.4 kg I should have finished with a weight not less than 56.1 kg

OK that's enough of that ... but it does illustrate that when people ask me (as they often do) how much weight do I lose during a 24 hour race, the answer is 'not as much as you might imagine'.

Now, the big day is Friday this week.  On that day I take the next, important step on the road to recovery.  I begin running again.  For the first fortnight or so it will only be alternating running and walking but it's a step in the right direction.  Although the ankle is no longer painful it does ache now and again.  I'm confident though that 40 minutes running and walking on Friday morning will be OK.

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