I recently bought a weighted vest to enhance my strength-building from walking and basic calisthenics, and wondered what data is out there on the effects of different loads. My vest has spots for 10 six-pound weights, so is adjustable up to 60 lbs in six-pound increments. Too much? Not enough? A quick search led me to this very well-written article containing more information than I had hoped for.
https://www.cnas.org/publications/reports/the-soldiers-heavy-load-1
RPG systems often ignore encumbrance because tracking it and calculating movement speeds detracts from fun gameplay for a lot of folks. Some systems (D&D) break encumbrance down into levels along the lines of "unencumbered", "light", "moderate", and "heavy", and describe how each level affects movement. Sometimes there is a label for the amount a character can lift off the ground that prevents any movement.
Heaven forbid a TTRPG track fatigue! I have on-and-off worked on developing my own system that simulates the real world better than other systems, and I have incorporated fatigue and recovery based on effort and fitness. I have to say that I managed to make a fatigue-tracking simulator that no one would enjoy playing. As many complaints as I have about D&D's class and level mechanics, I like the creative compromise between tracking fatigue or ignoring it (fire-and-forget spells/abilities). It is practical and playable to say that some activities (sprinting, max lifting) can be done "once per scene" or "once until a short rest".
The data I used for movements speeds all assumed being unencumbered, especially at higher speeds and distances. Elite runners wear shoes and clothing carefully designed to cut grams off of weight in order to provide a competitive edge. Competitive runners get lean. This soldier data is a treasure, showing realistic expectations for encumbered movement.
Valuable take-aways from this article:
- Characters should consider having an "approach" load and a "combat" load.
- Encumbrance causes initiative, reaction, awareness, concentration, and other penalties.
- Caloric intake, fatigue, and recovery time all scale with encumbrance.
- Encumbered people are easier to hit.
- There is a large increase in the time it takes to start moving from a standstill to 5m.
- 1/3 bodyweight is often used as a benchmark for the high end of a reasonable burden for a soldier.
Here are useful images from the article:
