In an 8-week study (Cahill et al. 2020), resisted sled pulls...
Fred Duncan@Fred__Duncan
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Nov 30, 2025
~1 min read
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In an 8-week study (Cahill et al. 2020), resisted sled pulls improved 5–20 m sprint times in every resisted group, while the unresisted group showed no change.
The heaviest loads (~75% velocity decrement) produced the largest gains in the first 10 m, along with the biggest
The heaviest loads (~75% velocity decrement) produced the largest gains in the first 10 m, along with the biggest
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increases in horizontal force (F₀). Power (Pmax) improved across all resisted groups.
→ Lighter loads bias velocity/rhythm.
→ Heavier loads bias force and projection.
Both matter if you want balanced acceleration.
If you want to understand how to load resisted sprints,
→ Lighter loads bias velocity/rhythm.
→ Heavier loads bias force and projection.
Both matter if you want balanced acceleration.
If you want to understand how to load resisted sprints,
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when to use them, and how to integrate them into a system for speed, it’s all inside Speed Kills, my 80+ page eBook and sprint program built around the science of sprint development.
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