Originally Posted By 41253
I'm pretty geeky even for an engineer so tested this hypothesis a while ago with a light running pack and a heart rate monitor. I jogged the same short loop four times in succession, alternating between not carrying and carrying a small pack weighing 10% of my body weight. I don't have the numbers any more but the indicated calories for the runs were something like 200,225,210,235. This suggested to me a 10% cost for the 10% extra weight coupled with a fatigue factor indicating decreasing efficiency with time. A more applicable test for hikers would be to do one walk per day with or without a back and maybe use a more realistic backpacking load at hiking speed.

Thoughts?


I'm surprised by your numbers. Not arguing or disagreeing, just surprised.

Many years ago I belonged to a gym with a variety of exercise machines that, among other thing, displayed calories burned. I also looked up the number of calories burned by activity on the internet (as we know everything on the internet is true). I performed the various exercises over several weeks and gauged how I felt. So, very subjective.

I determined that carrying 1% extra weight burned 5% more calories. So if one burned 100 calories per miles, a figure often cited for the average male, then carrying 10% of one's bodyweight should burn an extra 50% calories, so 150% of the baseline or 150 calories per mile. Carrying 20% of one's bodyweight, about what I carry for a backpacking trip, should burn 200 calories per mile. My more recent use of apps confirms this.

Using these figures, if one hikes 10 miles then one burns about 2000 calories. Add this to a baseline (for me) of around 2400 calories per day and one needs around 4400 calories per day to backpack 10 miles per day. Based on what I've read of thru-hikers (of which I am not, yet) this seems to be in the ballpark.

So those are my thoughts smile