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Uphill sprinting load- and force-velocity profiling: Assessment and potential applications
Jace A Delaney, Benjamin A McKay1, Jim Radcliffe1
1Department of Athletics, University of Oregon, Eugene, USA.
Journal of Sports Sciences
|November 3, 2021
Summary
The load-velocity (LV) relationship in hill sprinting is valid and reliable across various gradients. Increasing hill inclines decrease sprint velocity, with steeper slopes impacting athletes with higher horizontal force output.
Area of Science:
- Biomechanics
- Sports Science
- Exercise Physiology
Background:
- The load-velocity (LV) relationship is crucial for understanding sprint performance.
- Hill sprinting offers a variable resistance environment to study sprint mechanics.
- Quantifying the validity and reliability of LV relationships in hill sprinting is essential for training applications.
Purpose of the Study:
- To assess the validity and reliability of the load-velocity (LV) relationship during hill sprinting.
- To determine the impact of different hill gradients on sprint performance.
- To analyze how hill gradients affect sprint mechanics and force production.
Main Methods:
- Twenty-four collegiate athletes performed maximal sprints on flat terrain and hills (5.2%, 8.8%, 17.6%).
- Velocity-time data were collected using radar technology.
- Load-velocity (LV) relationships were derived from maximal sprint velocities; force-velocity-power (FVP) profiles from flat sprints.
Main Results:
- LV profiles demonstrated high validity (R² = 0.99) and reliability (TE < 4.4%).
- Sprint velocity decreased by an average of 1.7% for every 1-degree increase in slope.
- Steeper gradients affected athletes with greater horizontal force output at higher velocities.
- The tested hill gradients (<17.6%) provided insufficient resistance to optimize power development.
Conclusions:
- The load-velocity (LV) relationship is a valid and reliable method for assessing hill sprinting.
- Hill gradients significantly reduce sprint velocity, with greater impact on force-oriented sprinters.
- While not optimal for power, hills up to 17.6% can enhance late-stage sprint technique by promoting a horizontal body position.
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