The Study
Generation and modification of human locomotor EMG activity when walking faster and carrying additional weight
This study watched 11 women walk at different speeds and with different weights to see how their muscles and movements changed. It can show what happens when people walk faster or carry weight, but it can't prove exactly why those changes occur.
Analysis score
Maximum 44 for a cross-sectional study.
Where the score came from
When people walk faster or carry heavy things, their leg muscles work harder. Some muscles change a lot, others don’t. Your body uses different tricks depending on whether you're going fast, carrying weight, or doing both.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 527 / 100
Quality score
Snapshots of a population at a single point in time, or descriptions of small groups. Can identify correlations and prevalence, but cannot determine cause and effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Yes, these changes are meaningful—they show how your body adapts to real-life challenges like rushing or carrying groceries, mainly by turning up muscle power without changing how your legs move much.
- 2Walking at 1.5 m/s vs 1.0 m/s increases muscle activity by 56–133%, especially in calf muscles.
- 3Carrying 20.4 kg increases quadriceps and calf muscle activity by 24–43%.
- 4Doing both adds up for most muscles, but not the calf muscles when it comes to reflexes.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Experimental Physiology
Year
2025
Authors
Bridgette A P Damewood, T. Sinkjær, Aiko K. Thompson
Related Content
Claims (5)
When healthy women carry a heavy backpack—like 20 to 30 pounds—their leg muscles have to work a lot harder, especially the quads and calf muscles, but their walking motion stays pretty much the same.
When healthy women walk faster (about 3.4 mph instead of 2.2 mph), their leg muscles work a lot harder—some muscles more than double their activity—but the timing of how they fire stays the same.
When healthy women walk faster and carry extra weight at the same time, their hips and knees work harder in a predictable way, but their ankles react in a more complicated, less predictable way — suggesting the brain and spinal cord control these joints differently when both challenges are combined.
When healthy women walk faster—about 3.4 mph instead of 2.2 mph—their joints move through a bigger range and their steps get quicker, which helps them keep up the faster pace.
When women walk faster while carrying a heavy backpack, their calf muscles' automatic reflexes get stronger—but only if they're actually carrying weight. If they're just walking faster without extra load, the reflex doesn't change.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.