Being a type 1 diabetic my overriding concern when out on a
hike was how much carbohydrate (CHO) I’d need to keep me going, replace the glycogen
in my body, and prevent hypoglycaemia (dangerously low blood sugar levels).
Over the weekend, among many of the conversations I had, one
discussed weigh loss when on the trail. This got me thinking about the calorific
value of the food I pack, and whether it met the demands of a day’s hiking.
The starting point was to establish my BMR (basal metabolic
rate) this is an estimate of the minimum amount of calories needed to keep body
functioning whilst at rest. I used the one on the myfitnesspal website
here. Once
I’d established that figure, I found an Activity Factor formula which is a
basic multiplier of the BMR subject to the level of activity – see below.
Little/no exercise
|
BMR * 1.2
|
Light exercise
|
BMR * 1.375
|
Moderate exercise (3-5 days/wk)
|
BMR * 1.55
|
Very active (6-7 days/wk)
|
BMR * 1.725
|
Extra active (very active & physical
job)
|
BMR * 1.9
|
A simple Excel spreadsheet did the trick. I’ve highlighted
what I thought that would apply to time out hiking in the hills, and the
formula determined that I would need 2,900 calories to maintain that level of
activity. I then set about calculating how many calories I’d consumed listing
them in the same spreadsheet. The outcome was a bit of an eye opener – I was
short by circa 600 calories, that’s an approx. 20% shortfall. This probably is
a factor in how I’ve managed to stay trim – which isn’t a bad thing. Whilst
doing this exercise I also analysed the amount of CHO I consumed. This was also
very revealing as it indicated that I need to increase the amount of CHO
consumed at the end of the day, to top up the glycogen reserves, and to avoid an
overnight slingshot hypo (never a good thing, and potentially life threatening).
In this instance, the shortfall was made up with a portion
of chips and a few jars of cider. But going forward I’ll be re-introducing the
stalwart Bird’s Instant Custard as a pudding with a cake bar or similar, not
for the calories per se as I’d like to keep my figure, but for the necessary
CHO loading.