The Claim
For each additional kilogram of load carried during walking at 1.25 m/s, the mechanical work performed on the center of mass increases by approximately 1.40 W, and this increase accounts for a substantial portion of the elevated metabolic cost, with an observed delta efficiency of 15.6% between mechanical work and energy expenditure.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
When walking at 1.25 meters per second, carrying one extra kilogram of weight increases the mechanical work done on the body's center of mass by about 1.40 watts, and this increase explains 15.6% of the additional energy used.
See the scientific wording
The mechanical work performed on the center of mass during walking increases by approximately 1.40 W for each additional kilogram of load carried at 1.25 m/s, and this increase accounts for a substantial portion of the elevated metabolic cost, with an observed delta efficiency of 15.6% between mechanical work and energy expenditure.
When a person carries extra weight while walking, their body has to push and pull more mass with each step. This forces the ankle and knee joints to work harder to redirect the body’s motion, which makes the muscles use more energy. Muscles are not perfectly efficient, so the extra work they do burns more calories than the actual movement produces, and this difference explains most of the extra energy used.
What the research says
1 studyStudy: Mechanics and energetics of load carriage during human walking
When people walk with a heavier backpack, their bodies do more physical work to move forward, and this extra work explains most of the extra energy they use — about 16% of the extra calories burned come directly from moving the extra weight, just like the claim says.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.