[pct-l] food: proportion, calories, weight, 2 pounds meaning

[Yoshihiro Murakami]

I had read some hiker's opinions on  the dense food, calories, etc. I
could not agree with them but I was not able to find the opposite
evidences. But, recently noticed some. Due to my poor English ability,
I will mention briefly.

// Proportion of nutrition:

The calorie of protein should be taken from 10 to 15 percent. Suppress
the calorie of fat from 20 to 25 percent.  The calorie of the
carbohydrate is 60-70 percent. ( based on L Armstrong & C. Carmichael
" 7 weeks to the perfect ride" ).

Then the optimal calorie ratio is:
     carbohydrate : protein : fat = 60-70 : 10-15 : 20-25

When considering calorie ratio  carbohydrate : protein : fat = 4 : 4:
9  ( Kcal / gram )

Then the optimal weight ratio is :
   carbohydrate : protein : fat =   60-70:10-15: 9-11

When simplified fat to 10,
Then the optimal weight ratio is  60-70:10-15: 10

---- This weight ratio may be the best  for long distance hiker.  Much
of the component of the muesli are near to this weight ratio. So, we
can change this ratio slightly by adding milk or oil.


// calorie per gram

When  this ratio was applied  to the dry food, then the total calorie
can be calculated as follows:

The calorie of carbohydrate and protein  is equal, then  90% is 4Kcal
/gram, 10% is 9Kcal/gram. When we have 1 gram dry food, we have total
4.5 Kcal.

// calorie consumption when hiking

I cannot find the good article ( now ), but there is a calculation
equation in Japanese site:
When we are climbing a mountain, energy consumption is approximately
0.155 Kcal / 1 Kg( body weight )/ one minute. This value may be
modified by time, age, gender, etc. The calculation equation is as
follows:

Energy consumption = 0.155 X body weight(Kg) X minutes X constant:

                 male     female
constant      1          0.95   ( age 20-29 )
                  0.96     0.87    ( age 30-39 )
                  0.94     0.85    ( age 40-49 )

When you are a 35 years old 60 Kg(132pound)  male, and when you hiked
for eight hours, then the energy consumption will be:

0.155 X 60 X (60 X 8 ) X 0.96 =4285 Kcal

I am 61 years old and 77 Kg (170 pound ) , and when I  hiked for eight
hours, then the energy consumption will be:

0.155 X 77 X (60 X 8 ) X 0.94(?)= 5385 Kcal

// weight of dry food per day

We have calculated the calorie of food: 4.5 Kcal /gram. When 4300Kcal
was needed in a day, the weight of food is 4300 /4.5 =956gram ( 2.1
pound)/day.

In my case, I need 5400Kcal per 8 hours, so the weight of food is
5400/4.5 = 1200gram (2.6 pound )/day.

This may be the meaning of 2 pounds. If I have idling time, I will
search more firm evidences.









-- 
Sincerely
--------------- --------------------------------------
Hiro    ( Yoshihiro Murakami )
Blogs http://completewalker.blogspot.com/
Photo http://picasaweb.google.co.jp/CompleteWalker/
Backpacking since about 1980 in Japan
2009 JMT, the first America.
2010 JMT, the second America.
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