MTNMetrics applies published research on loaded walking to route and profile inputs, including pack weight, terrain, pace, and grade.
Rules of thumb can be useful, but they do not describe every trip. A planning estimate can consider:
A 120 lb ultralight hiker with a 15 lb pack on a flat trail has very different calorie needs than a 200 lb hunter with a 60 lb pack climbing 4,000 feet. Yet the "2 lbs per day" rule treats them the same.
These inputs help turn a broad rule of thumb into a trip-specific estimate. Actual needs still vary with conditions and the individual hiker.
LCDA stands for Load Carriage Decision Aid. It's a metabolic prediction equation developed by the US Army Research Institute of Environmental Medicine (USARIEM) specifically for predicting energy expenditure during loaded marches.
The model describes the added demands of carrying a load while walking. MTNMetrics combines those published inputs with the route and profile details you provide.
The research was published in Medicine & Science in Sports & Exercise in 2022 after comparison with measured energy expenditure. That research gives MTNMetrics a foundation designed specifically for walking with a loaded pack.
MTNMetrics combines load-carriage research with terrain and grade adjustments to reflect the demands of your route.
Body mass is one of the inputs used to estimate the energy required for loaded walking.
The load you carry is included alongside body mass and route details.
Pace affects both the modeled energy cost and the time spent hiking.
The terrain category you select changes the model input for surface conditions.
The model distinguishes route grade rather than treating every mile alike.
These coefficients are model inputs derived from published terrain research. They compare each listed surface with paved road; real trail conditions can differ.
| Terrain | Coefficient | Impact |
|---|---|---|
| Paved Road | 1.0 | Baseline |
| Grass | 1.08 | +8% energy |
| Dirt Road | 1.2 | +20% energy |
| Trail | 1.15 | +15% energy |
| Light Brush | 1.15 | +15% energy |
| Heavy Brush | 1.35 | +35% energy |
| Packed Snow | 1.3 | +30% energy |
| Sand | 1.5 | +50% energy |
| Loose Snow | 1.5 | +50% energy |
| Swamp | 3.5 | +250% energy |
Looney DP, Santee WR, Karis AJ, Blanchard LA, Rome MN, Carter AJ, Potter AW. Modeling the Metabolic Costs of Heavy Military Backpacking. Med Sci Sports Exerc. 2022 Apr 1;54(4):646-654.
Additional research incorporated into our model includes terrain coefficients from Pandolf et al. and grade adjustment factors from Santee et al.
MTNMetrics provides calorie estimates based on peer-reviewed research to help with trip planning. These are estimates only—individual energy expenditure varies based on fitness level, efficiency, altitude acclimatization, weather conditions, and other factors not captured by any equation.
The LCDA equation was developed for military load-carriage applications. Use your estimates alongside your experience and current trail conditions when planning food.
MTNMetrics is not affiliated with or endorsed by the U.S. Department of Defense or the U.S. Army Research Institute of Environmental Medicine.
Use the model on your trip
Build and save routes, see daily calorie targets, and find foods by name or barcode. Track meal-pack calories, macros, and food weight. Map layers include public lands, slope angle, and active wildfire perimeters.
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