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Published on: May 1, 2018
Fast unilateral isometric knee extension torque development and bilateral jump height
Cornelis J de Ruiter1, Daniel Van Leeuwen, Arjan Heijblom
1Institute for Fundamental and Clinical Human Movement Sciences, Vrije University, Amsterdam, the Netherlands. C_J_de_Ruiter@FBW.VU.NL
Medicine and Science in Sports and Exercise
|October 5, 2006
Summary
The initial rate of leg muscle torque development, specifically the torque time integral for the first 40 milliseconds (TTI-40), significantly predicts jumping performance. Fast neural activation is key for both isometric contractions and dynamic jumping ability.
Area of Science:
- Biomechanics
- Human Movement Science
- Sports Physiology
Background:
- Understanding the determinants of explosive power is crucial for athletic performance.
- The rate of torque development is a key factor in dynamic movements like jumping.
- Neural activation plays a significant role in muscle force production.
Purpose of the Study:
- To investigate if the initial rate of unilateral knee extensor torque development (first 40 ms) depends on fast neural activation.
- To determine if this initial torque rate predicts bilateral jumping performance.
Main Methods:
- Nine males performed unilateral fast isometric knee extensions and bilateral squat jumps (SJ) and countermovement jumps (CMJ).
- Torque time integral for the first 40 ms (TTI-40) and EMG for 40 ms before contraction (EMG-40) quantified initial torque rise and neural activation.
- Contractions were performed from relaxation or with pre-tension.
Main Results:
- TTI-40 was significantly related to EMG-40, indicating dependence on neural activation.
- Jump height in both SJ and CMJ was significantly correlated with TTI-40.
- No significant correlation was found between maximal isometric torque (Tmax) and jump height.
Conclusions:
- The initial rate of torque development (TTI-40) largely explains variations in jump height.
- The capacity for rapid neural activation is a dominant factor in both isometric and dynamic movements.
- This highlights the importance of neural drive for explosive athletic performance.
