Sled Work (Pushes, Pulls, Resisted Marches)

Sled work uses a weighted sled (or prowler) that the athlete pushes, tows (harness/belt), or marches with to add external resistance to running and the acceleration drive. It exaggerates the forward lean, long ground contact, and horizontal force application of the acceleration phase, making it a primary tool for resisted-assisted-sprinting and lower-body power/conditioning.

Technique: maintain the acceleration posture — body in a forward-leaning line, powerful triple-extension push of the drive leg, full strides, sharp arm action (for tows). Keep the lean and shin angle; don't let heavy loads pull the hips down or shorten steps into a "grind."

Loading is the key variable and is debated:

• Light sleds (≈ up to ~10% of body mass, causing <~10% velocity loss) preserve near-normal sprint mechanics and bias max-velocity / speed.
• Heavy sleds (large velocity loss, sometimes 50%+ of body mass) strongly bias acceleration, horizontal force, and strength-speed but distort mechanics the most.

For power/speed, use short distances (~10-30 m) with full recovery; for conditioning, longer/heavier repeats with shorter rest.

• Push/tow/march a weighted sled to resist the acceleration drive.
• Exaggerates forward lean, long contacts, and horizontal force.
• Light loads (~≤10% BW) bias speed; heavy loads bias acceleration/horizontal force.
• Keep acceleration posture; avoid loads that "grind" mechanics.
• Power/speed: short distances + full recovery; conditioning: longer/heavier repeats.

• resisted-assisted-sprinting — sleds are the main resisted-sprint method.
• acceleration-vs-max-velocity — load shifts the emphasis between phases.
• sprint-mechanics — sled work overloads the drive-phase pattern.
• wall-drills — unloaded teaching of the same drive position.
• gluteus-maximus / quadriceps — prime push movers.