Wednesday, 25 March 2015

London to Brighton Training: Thinking About Food and Weight: Part 2

So how many calories do I get through in a "typical" day?

I know we are all a bit different, and have different metabolisms, etc. etc., but let's just assume for a moment that I am "average" - we can look at any differences I have a bit later.

So how much energy (calories) do different tasks take up, for the "average" person?

I am sure you will find lots of charts and tables out there in "Internet Land".
I will be looking at one of them in this post: the one on the Harvard Medical School website.

It is important to use a "decent" source, as there is nothing to stop anyone (even me!) just making up a table that fits my own likes and dislikes, and publishing that. Just because it is on the Internet does not mean it is scientific or "reliable" - it can just be someone's personal opinion, and no more than that. Would you, say, spend a week eating just carrots, because someone you never met and know nothing about said it was good for you?

Example: I don't like chicken, so I'll put that one down as bad for folks, but I do like cheese, so I'll say that one is good for you, and you ought to eat more of it for the calciun abd protein content etc. But does it make it true just because I like it?
There is a foolish internet poster out there, with no scientific qualifications at all, that has decided that chicken liver is the best thing to eat - after all, look at all that vitamin A, right? That foolish poster is even an occasional columnist for a national newspaper. No doubt she is an entertaining and engaging writer, but that doesn't mean she knows what she is talking about. Entertainment and education are not always the same thing!
What she fails to mention is that too much Vitamin A has some scientifically acknowledged side effects (no surprise there!), including, in extreme cases, making the skin on the bottom of your feet fall off (this actually happened to some polar explorers who were shooting and eating part of their food!).
Indeed, the well-regarded Mayo Clinic has a long list of problems that too much Vitamin A can cause/exacerbate, particularly for smokers, heavy drinkers, and expectant mothers ...

So it is important to rely on "reputable" sources, rather than the opinions of well-known folks that don't know what they are talking about.

Certainly Harvard Medical School is, we all agree, pretty reputable. As is the Mayo Clinic.
Wikipedia can be a bit variable - most of the stuff on there is very good indeed, but sometimes one comes across complete rubbish due to the fact that Wikipedia articles are written by a variety of contributors, some of whom are well-meaning, but just don't understand the science behind what they are writing, and some of whom are trying to push a particular viewpoint.

Anyway, back to the plot ...
What do I do in a typical "work day"?
I get up at about 04:30, get a bit of breakfast and a mug of tea, then read the news and blog until about 05:30. Then I get ready for work and leave just after 06:00.
A ten-minute cycle (less if I go faster) gets me to work, where I spend the next 3 1/2 hours doing various active "office" work - not much sitting about reading emails for me - at least not at work!
then it is about 3 1/2 hours of walking about, not particularly quickly, talking to a few folks, etc. etc.,
then it is home for a 1 3/4 hour lunch (lucky me) then it is back for another 2 1/2 hours, finishing a little after 18:00, then home to relax, see my daughter, and eat, and bed by 20:30.
What a thrilling life I lead :-)

So let's break that down into parts.
8 hours asleep
1 hours computer work
30 mins standing
10 mins cycling at a modest pace
3 1/2 hours active "office work"
3 1/2 hours walking and standing
15 minutes cycling (I like to get an extra mile in on the way home)
1 3/4 hrs mixed sitting and standing
10 mins cycling at a modest pace
2 1/2 hours mixed driving and walking
15 minutes cycling (I like to get an extra mile in on the way home)
2 1/2 hours mixed sitting and standing
bedtime, and back to the top of the list.

So how many hours is that?
8hrs+1hrs+30 mins+10 mins+3 1/2hrs+3 1/2hrs+15 mins+1 3/4hrs+10mins+2 1/2hrs+15mins+2 1/2hrs = 24hrs 5 minutes. Let's just assume that I sit about for the 5 minutes less in the evenings! :-)
The "Harvard" chart only goes up to 185 lbs, and I am 20 lbs or more heavier than that.
But let's just use those figures and make an adjustment at the end.
Remember also that the Harvard chart is in half-hour blocks, so hours half to be multiplied by 2!

  1. 8 hours asleep = 2 x 8 x 28 calories = 448 calories
  2. 1 hours computer work = 2 x 61 = 122 calories
  3. 30 mins standing = 56
  4. 10 mins cycling at a modest pace = problems - because I cycle to work quite a bit SLOWER than the figures given in the chart. So I will divide the slowest cycling figure by a bit more than 2 to give a "guesstimate" of about 50 calories (!)
  5. 3 1/2 hours active "office work" 2 x 3.5 x well, I'm stuck again, because I don't spend my time stuck at a desk ... I used to drive trucks and that was certainly no more physical than what I do now (yes, I still do a bit of lifting!), so I will take that figure as a "guesstimate" - 2 x 3.5 x 89 = 623 calories
  6. 3 1/2 hours walking and standing - hmm - I'll divide this evenly between "standing in line" and walking - so I get 2 x 3.5 x (56+178)/2 = 819 calories
  7. 15 minutes cycling (I like to get an extra mile in on the way home) - from above, I will use the same methodology to give me 1.5 x 50 = 75 calories
  8. 1 3/4 hrs mixed sitting and standing - I'll divide this evenly between "standing in line" and light office work - I am certainly not sedentary watching TV (!) - so I get 2 x 1.75 x (56+67)/2 = 215 calories
  9. 10 mins cycling at a modest pace = 50 calories again (see calculation above)
  10. 2 1/2 hours mixed driving and walking. I'll split that between walking and truck driving (remember, I used to actually be a truck driver, so I know what it feels like!) 2 x 2.5 x (89+178)/2 = 667 calories
  11. 15 minutes cycling (I like to get an extra mile in on the way home) = 75 calories again (see calculation above)
  12. 2hrs 25 mins hours mixed sitting and standing (remember the extra 5 minutes I had to take off!) - using the methodology above, I have 2 x 2 25/60 x (56+67)/2 = 297 calories.
So, for a "typical" working day I have 448 + 122 + 56 + 50 + 623 + 819 + 75 + 215 + 50 + 667 + 75 +297, for a total of 3497 calories.
If that sounds high to you, then I should let you know that one of my co-workers has his smartphone set to a target of 15,000 steps a day, and he achieves it, and he doesn't do the 2 1/2 hours afternoon/evening section that I do (it is paid overtime!). I seem to remember that the recommendation is 10,000 steps a day - well, folks like me pass that easily, and push up towards twice that figure (!)

So clearly the "recommended" numbers of 2000 to 2500 calories a day are completely inappropriate for me - I'd waste away, and be VERY tired for the latter part of my working day.

But there is more, Note how the various figures in the Harvard table increase with body weight - by about 25% from the column for 125 lbs folks to 155 lbs folks, and by about another 20% to make up the 185 lbs folks column. So it is reasonable to assume that as I am 20 to 25 lbs heavier than the 185lb column, I am using even more calories. One might guess the "calorie" rise from 185 lbs to 215 lbs as being 15% (a nice 25, 20, 15 progression for every extra 30 lbs in bodyweight), so as I am only 20 to 25 lbs more, I will adjust my daily total upwards by the lower figure of 10%,
3497 x 1.1 = 3846 calories.

So I calculate, using a variety of "reasonable" assumptions, that on a typical working day, if I have an "average" metabolism, etc. etc. I use about 3850 calories.

I don't get much training in on "working days" - sometimes I get an afternoon off, and then the missing "work" calories" tend to be made up by extra "training" - running, cycling, that sort of thing. Same goes for the weekends.

That's me.
What about you?
How many calories do you think YOU use in a day?

And what does this have to do with the London to Brighton Bike Ride?
Well, as I have outlined above, having an active job gives me a "hidden" core of training and fitness that is underlying the sometimes modest "training" efforts I make - if you have an office job, and just watch TV in the evening, you are going to have to put in a LOT more training hours than me (!)

Remember, I am used to being quite active for 12 hours (with some breaks) in a day.
Are YOU?

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