Calculate Your Metabolic Equivalent Task (MET)?
It is important to understand how many calories you will likely burn on your hike. Different daily activities burn calories at different rates. These metabolic differences in activities are classified as metabolic equivalent tasks or MET values. Hundreds of different activities have corresponding MET values as illustrated by the referenced physical activities. The more strenuous the activity the higher the MET value. Below is a short list of MET values.
Metabolic Equivalent Task Values
Calculating Calories Burned
To calculate the calories burned multiply the MET value by your weight in pounds times 0.4536 (conversion factor from pounds to kilograms). For example, to compute the calorie expenditure for a 154.3 pound person, backpacking (7.0 MET) for 8 hours would result in 3,920 calories (7 x 154.3 x 0.4536 x 8 h) consumed.
Calories Burned = MET value x Body Weight in Pounds x 0.4536 x Duration in Hours
As you can see from the above Metabolic Equivalent Task Value chart, calorie consumption is also dependent on pack weight when climbing hills. The MET value increases as the pack weight increases. I used the MET value of 7.0 for general backpacking which considers both climbing hills and descending with a moderate pack load for the calculations below. The chart below shows the calories burned per hour for three of the most common hiking activities: backpacking, sleeping, and resting.
Calories Burned per Hour by Activity
To estimate the number of calories burned in an entire day, each activity during the day should be considered along with how long that activity occurred. For estimating the daily calorie rate, the daily activities used were the number of hours backpacking, and eight hours of sleep and rest. It was calculated that a 150-pound person will burn about 5,062 calories while backpacking for eight hours in a day.
Calories Burned in a Day = Calories Burned Backpacking + Calories Burned Sleeping + Calories Burned Resting
Daily Calories Burned & Trail Hours
Daily Calories Burned While Backpacking is Staggering!!
The difference between backpacking with a heavy pack and a light pack is substantial. But most people do not consider the impact of carrying a heavier pack in terms of calories or energy consumed. Below is a chart comparing the estimated calories burned to hike for five months using a light pack versus a heavy pack.
Estimated Calories Burned on a 5-Month Thru-Hike
Understanding your calories burned while hiking will make it easier to plan your next backpacking trip. Most long-distance backpackers do not eat enough while in the outdoors but make up for the calorie deficit when they return to town to resupply.
All of that being said, the important things to consider when planning your diet is not just the amount of calories you will need to replenish but the quality of those calories as well!