Hiking Distance Estimates

Paul Petzoldt, a mountaineer and founder of the National Outdoor Leadership School (NOLS) in 1976 proposed a theory to help backpackers plan trips and calculate their energy needs while on the trail in his book, Teton Trails. His theory states that one energy mile is equal to the energy required to walk one mile on flat terrain. He also said that you need to add two energy miles for every 1000 feet of elevation gain. In other words, if you hiked one mile while climbing 1000 feet, you would've used the equivalent of three energy miles.

Petzoldt's theory had never been tested before. That is until 2010, when a study was conducted at Western Carolina University's Exercise Physiology Laboratory, by Maridy Troy, assistant professor in WCU’s health and physical education program, and Maurice Phipps, professor of parks and recreation management.

The study measured the energy cost and perceived exertion for walking on flat terrain, with and without a backpack, as well as an elevation gain of 1000 feet. Results from the data show an average of a 1.6-mile equivalent for a 1000 foot gain in elevation. Differences between females and males ranged from 1.32 to 2.02. Professor Phipps stated in an article for WCU news that the range revealed by the study was due to the “hikers” personal weight differences. The abstract from the study states that further research using heavier expedition packs at higher altitudes could also reveal changes in energy cost as well.

"It is remarkable that Petzoldt’s energy mile theory is so close to the actual energy cost measured during our study," Phipps stated. He also said the energy required for hiking up steep mountain trails would vary for individuals and groups, and the variables of the trail would also factor in, but he recommends that backpackers stick with Petzoldt's theory of adding two energy miles for every 1,000 feet in elevation gain.

This formula has allowed me to roughly gauge the relative difficulty trails.

RogerDoger — Good to know, thanks.

>"His theory states that one energy mile is equal to the energy required to walk one mile on flat terrain. He also said that you need to add two energy miles for every 1000 feet of elevation gain."

This is the same math I worked out for myself 35 years ago.

>"Petzoldt's theory had never been tested before."

I feel like I've been testing it for 35 years now. But, qualitatively through exhaustion, aches, pains, bonking, and sometimes by finishing a death march still feeling great. Nice that someone tested it qualitatively.

>"Western Carolina University's . . . study . . .results . . . males . . . to 2.02 (horz miles per 1000 vertical feet).

"It is remarkable that Petzoldt’s energy mile theory is so close to the actual energy cost measured during our study," I too, arrived at 2.00

To paraphrase the A-Team's John "Hannibal" Smith, "I love it when an estimate comes together".

While Petzoldt counts only vertical gain towards energy expended, I also count vertical loss. I realize vertical loss doesn't use as much energy as vertical gain (but more than horizontal miles), but vertical loss does cause more soreness and injuries than going up or level so I count it the same as vertical gain and consider the resulting "equivalent miles" as a composite of energy expended, tiredness, soreness and time in transit.

"Book time" for the AMC white mountain guide (NH) is 30min per mile plus 30min per 1000' gained. I tend to add it to going down rather than up.

for calculating mileage i use a calculator and add up the section distances labels on my map :) http://img.photobucket.com/albums/v115/Socjake/Hiking/Owlshead.jpg