Related Experiment Video
Updated: Dec 11, 2025
07:30
Muscle Imbalances: Testing and Training Functional Eccentric Hamstring Strength in Athletic Populations
Published on: May 1, 2018
15.7K
Optimal load for a torque-velocity relationship test during cycling.
Renata L Krüger1, Arthur Peyrard2, Hervé di Domenico2
1Human Performance Laboratory, University of Calgary, 2500 University Drive NW, Calgary, T2N 1N4, Canada.
European Journal of Applied Physiology
|August 21, 2020
Summary
Optimal load during single sprints improves torque-velocity (T-V) and power-velocity (P-V) relationships. Reducing the optimal load post-fatigue further enhances these neuromuscular force assessments.
Area of Science:
- Sports Science
- Biomechanics
- Exercise Physiology
Background:
- Accurate assessment of lower limb neuromuscular force capabilities is crucial for performance.
- Single sprint testing requires good data fit in torque-velocity (T-V) and power-velocity (P-V) relationships for reliability.
Purpose of the Study:
- To compare the goodness of fit of single sprints using traditional vs. optimal loads.
- To determine if reducing the load in a fatigued state improves T-V and P-V relationship fit.
Main Methods:
- Thirteen participants completed sprints pre- and post-fatigue.
- Loads tested included traditional (TRAD), optimal (OPT), and a reduced optimal load (LOW-OPT) post-fatigue.
Main Results:
- Optimal load sprints showed a better T-V relationship fit (higher R²) and faster time to maximal power (Pmax) pre-fatigue compared to traditional loads.
- Post-fatigue, the reduced optimal load (LOW-OPT) yielded a greater velocity spectrum and reduced time to Pmax compared to traditional and optimal loads.
Conclusions:
- Single sprints using optimal loads, and reducing this load post-fatigue, enhance the goodness of fit for T-V and P-V relationships.
- Load selection for sprints should be individualized based on force production capacity, not solely body mass.
Related Concept Videos
01:10Torque
21.1K
Torque is an important quantity for describing the dynamics of a rotating rigid body. We see the application of torque in many ways in the world, such as when pressing the accelerator in a car, which causes the engine to apply additional torque on the drivetrain. Here, we define torque and provide a framework to create an equation to calculate torque for a rigid body with fixed-axis rotation.
Torque can be considered as the rotational counterpart to force. Since forces change the translational...
Torque can be considered as the rotational counterpart to force. Since forces change the translational...
21.1K
01:19Net Torque Calculations
10.9K
When a mechanic tries to remove a hex nut with a wrench, it is easier if the force is applied at the farthest end of the wrench handle. The lever arm is the distance from the pivot point (the hex nut in this case) to the person’s hand. If this distance is large, the torque is higher. Only the component of the force perpendicular to the lever arm contributes to the torque. Therefore, pushing the wrench perpendicular to the lever arm is more advantageous. If multiple people apply force to...
10.9K
01:13Angle of Twist: Problem Solving
636
An electric motor applies a torque of 700 N·m to an aluminum shaft, triggering a stable rotation. Two pulleys, B and C, are subjected to torques of 300 N·m and 400 N·m, respectively. The modulus of rigidity is provided as 25 GPa. With the knowledge of the length and diameter of each segment, the twist angle between the two pulleys can be computed. First, a section cut is made between pulleys B and C, and the cut cross-section is analyzed using a free-body diagram. Given that the torque...
636
01:09Transmission Shafts: Problem Solving
433
Designing a solid shaft that transmits power from a motor to a machine tool involves a series of calculations to ensure the shaft can withstand the stresses applied by bending moments and torques. First, calculate the torque exerted on the gear, considering the power transmitted by the shaft and its rotational speed. Following this, compute the tangential forces acting on the gears, which directly relate to the torque and the gear radius.
Next, use bending moment diagrams for the shaft to...
Next, use bending moment diagrams for the shaft to...
433
01:15Design of Transmission Shafts - Stress Analysis
643
Designing a transmission shaft requires a thorough understanding of the stresses induced by bending moments and torques, especially in systems where power is transferred through gears. These forces create force-couple systems at the centers of the shaft's cross-sections, leading to both transverse and torsional loading. Although shearing stresses from transverse loads are typically smaller than those from torques and are often overlooked, the significant normal stresses from these loads...
643
01:16Design of Transmission Shafts
637
The design of a transmission shaft is governed by two primary specifications: the power it transmits and its rotational speed. These parameters guide the selection of the shaft's material and cross-sectional dimensions, ensuring that the material's maximum shearing stress remains within the elastic limit while transmitting the desired power at the given speed. The system's power is intrinsically linked to the applied torque. The torque applied to the shaft can be calculated by reconfiguring the...
637