Why Fitness Watches Disagree
If you track the exact same 3-hour hike with an Apple Watch, a Garmin watch, and Strava, you will often see different calorie numbers. This is usually not an error; it simply comes down to whether the app reports Total Calories or Hiking-Only (Active) Calories.
Apple Watch: Active First
Apple Watch shows Active Calories prominently in red on your Move ring. It calculates your resting calorie rate and subtracts it so you only see the extra calories from hiking.
Garmin & Strava: Total by Default
Garmin, Strava, and most gym machines report Total Calories as their main number. They give you credit for all calories your body burned during the time you were out on the trail.
Hikers planning their trail food often make a simple math mistake: they take the Total Calories from their watch and add it directly to their normal full-day calorie budget. This accidentally counts resting calories twice!
Example of Double Counting:
• Normal daily resting & living budget: 2,000 kcal
• 4-hour hike reported on watch (Total): +1,600 kcal
✕ If you eat 2,000 + 1,600 = 3,600 kcal, you counted 4 hours of resting burn (~320 kcal) twice!
✓ True Daily Need = 2,000 (Daily) + 1,280 (Hiking Only) = 3,280 kcal.
How the Math Works
In sports science, physical activity is rated in energy multiples (METs). A score of 1.0 represents resting quietly:
When an activity has an energy rating of 6.0 (like mountain hiking), exactly 1.0 covers your body's natural resting needs, and 5.0 represents the extra physical work of climbing hills, carrying gear, and walking the trail.