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Updated: Jun 11, 2025
07:24
A Method for Quantifying Upper Limb Performance in Daily Life Using Accelerometers
Published on: April 21, 2017
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A comparison of weighted countermovement jumps loading modes using wearable accelerometers
V Radulovic1, D Kwong1, A Green1
1Department of Sport and Movement Studies, Faculty of Health Sciences, University of Johannesburg, South Africa.
South African Journal of Sports Medicine
|October 2, 2024
Summary
External loads alter countermovement jump (CMJ) kinetics, with dumbbell CMJs maximizing force and power, while trapezius barbell CMJs enhance velocity and acceleration. This informs individualized athlete training programs.
Area of Science:
- Biomechanics
- Sports Science
- Exercise Physiology
Background:
- The countermovement jump (CMJ) is crucial for assessing athletic performance and power development.
- External loads can enhance CMJ testing but may alter jump kinetics due to center of mass displacement.
Purpose of the Study:
- To evaluate the kinetic responses to incremental external loads across different loading methods (barbell, trapezius barbell, dumbbell) during CMJs.
Main Methods:
- Thirty-two male athletes performed weighted CMJs (20, 40, 60 kg) using three loading modes.
- Jump metrics were captured using wearable accelerometers.
- Repeated measures ANOVA analyzed differences in jump kinetics (p<0.05).
Main Results:
- Increased external loads significantly altered CMJ kinetics across all loading modes (p<0.001).
- Different loading modes produced distinct kinetic profiles: dumbbell CMJs yielded highest force and power, while trapezius barbell CMJs resulted in greater velocity and acceleration (p<0.001).
- Standard barbell CMJs did not yield the highest kinetic outputs.
Conclusions:
- CMJ kinetics are significantly influenced by both external load magnitude and the type of loading implement.
- Varying loading methods allow for targeted development of specific jump performance variables, enabling personalized training strategies for athletes.
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