JAK
2007-06-24, 12:56
I've got this new idea for estimating food, for a given trip, or alternatively for estimating time for a given trip. It might seem oversimplified, but I am wondering if it might work for most people once it is calibrated with better data. It works something like this:
FOOD[lbs] = (DISTANCE[miles]/12 + GAIN[km]) x WEIGHT[lbs]/200
where:
FOOD = weight of food in pounds
DISTANCE = distance travelled in miles
GAIN = cummulative elevation gain in kilometers
WEIGHT = average weight of hiker plus gear plus consumables
Most notably it doesn't worry about how fast you are travelling, or how long you are stopping each night, or how fit you are or even how much body fat you are burning. It assumes you are travelling at a pace that is about right for you, but that you are more intent on covering distance than camping too much along the way. Campers might add a pound of food per day, which they tend to do anyways. The reason I think it might work well is those of us that are overweight tend to travel slower and perhaps rest longer and so we probably burn more calories when stopped relative to the distance we travel each day, but we also tend to have more fat to burn and more time to burn it, so I think these two things tend to cancel out. The other assumption is that the food is about 3-4 kcal/gram, or 1300-1800 kcal/pound. Again, fitter people might have less fat to burn, but they can include more fat in their diet which increases the kcal/gram, so it might work out even, more or less.
Anyhow, the same formula might be used to estimate how much time a segment might take. Most people eventually figure out how much food they are capable of eating each day. For most people it might be 2 pounds/day, but for naturally larger people, or even smaller people well trained, this could go up to 3-4 pounds or more. So instead of estimating food for a given leg, based on estimated duration, you might be better to estimate the duration based on the estimate of food requirements for that segment.
e.g.
60 miles with 5 km cumulative elevation gain.
Hiker#1
220 pounds of hiker, gear, food, water, on average.
say this hiker needs 2.2 pounds/day at their prefered pace.
FOOD = (60/12 + 5) x 220/200 = 11 lbs of food
TIME = 11/2.2 = 5 days (12 miles/day)
Hiker#2
150 pounds of hiker, gear, food, water, on average.
say this hiker needs 2.5 pounds/day at their prefered pace.
FOOD = (60/12 + 5) x 150/200 = 7.5 lbs of food
TIME = 7.5/2.5 = 3 days (20 miles/day)
Would this simple formula work for most people with some tweaking? Is there a database available with hiker weights and food consumption for various segments of the Appalachian trail, or other trails or trip reports?
FOOD[lbs] = (DISTANCE[miles]/12 + GAIN[km]) x WEIGHT[lbs]/200
where:
FOOD = weight of food in pounds
DISTANCE = distance travelled in miles
GAIN = cummulative elevation gain in kilometers
WEIGHT = average weight of hiker plus gear plus consumables
Most notably it doesn't worry about how fast you are travelling, or how long you are stopping each night, or how fit you are or even how much body fat you are burning. It assumes you are travelling at a pace that is about right for you, but that you are more intent on covering distance than camping too much along the way. Campers might add a pound of food per day, which they tend to do anyways. The reason I think it might work well is those of us that are overweight tend to travel slower and perhaps rest longer and so we probably burn more calories when stopped relative to the distance we travel each day, but we also tend to have more fat to burn and more time to burn it, so I think these two things tend to cancel out. The other assumption is that the food is about 3-4 kcal/gram, or 1300-1800 kcal/pound. Again, fitter people might have less fat to burn, but they can include more fat in their diet which increases the kcal/gram, so it might work out even, more or less.
Anyhow, the same formula might be used to estimate how much time a segment might take. Most people eventually figure out how much food they are capable of eating each day. For most people it might be 2 pounds/day, but for naturally larger people, or even smaller people well trained, this could go up to 3-4 pounds or more. So instead of estimating food for a given leg, based on estimated duration, you might be better to estimate the duration based on the estimate of food requirements for that segment.
e.g.
60 miles with 5 km cumulative elevation gain.
Hiker#1
220 pounds of hiker, gear, food, water, on average.
say this hiker needs 2.2 pounds/day at their prefered pace.
FOOD = (60/12 + 5) x 220/200 = 11 lbs of food
TIME = 11/2.2 = 5 days (12 miles/day)
Hiker#2
150 pounds of hiker, gear, food, water, on average.
say this hiker needs 2.5 pounds/day at their prefered pace.
FOOD = (60/12 + 5) x 150/200 = 7.5 lbs of food
TIME = 7.5/2.5 = 3 days (20 miles/day)
Would this simple formula work for most people with some tweaking? Is there a database available with hiker weights and food consumption for various segments of the Appalachian trail, or other trails or trip reports?