Related Experiment Video
Updated: Jul 5, 2025
08:08
Oscillation and Reaction Board Techniques for Estimating Inertial Properties of a Below-knee Prosthesis
Published on: May 8, 2014
16.8K
Effect of Randall foils on the rowing propulsive cycle
Ricardo Cardoso1,2, Pedro Fonseca2, Márcio Goethel1,2
1Centre of Research, Education, Innovation and Intervention in Sport, Faculty of Sport, University of Porto, Porto, Portugal.
Sports Biomechanics
|January 19, 2024
Summary
The addition of Randall foils to rowing Big blades enhances force application during rowing. These foils positively impact the force-time curve, potentially improving overall rowing performance.
Area of Science:
- Sports Science
- Biomechanics
- Engineering
Background:
- Rowing performance is significantly influenced by the design of rowing equipment, specifically the blades.
- The Randall foil, a spoon-shaped modification, has been recently introduced to the top edge of rowing Big blades to potentially enhance performance.
Purpose of the Study:
- To analyze the differences in force-related variables between rowing Big blades with and without Randall foils.
- To investigate the impact of Randall foils on the force-time curve during maximal effort rowing.
Main Methods:
- Nineteen rowers participated in the study.
- Rowers performed two 90-second bouts of maximal effort tethered rowing.
- Force-related variables, including cycle average peak force, propulsive cycle average time, and rate of force development, were measured and compared between Big blades with and without Randall foils.
Main Results:
- Significant differences were observed in cycle average peak force, propulsive cycle average time, and rate of force development between Big blades with and without Randall foils.
- Specifically, Big blades with Randall foils showed a different force application profile compared to those without.
- Differences in cycle average peak force were also noted during the middle and final phases of the rowing effort.
Conclusions:
- The data suggest that Randall foils have a positive effect on the force-time curve profile in rowing.
- These findings indicate a potential benefit of using Randall foils for improving rowing performance.
- Further research is recommended to evaluate the influence of Randall foils on actual on-water rowing conditions.
Related Concept Videos
01:15Thin-Walled Hollow Shafts
192
In analyzing a thin-walled hollow shaft subjected to torsional loading, a segment with width dx is isolated for examination. Despite its equilibrium state, this segment faces torsional shearing forces at its ends. These forces are quantitatively described by the product of the longitudinal shearing stress on the segment's minor surface and the area of this surface, leading to the concept of shear flow. This shear flow is consistent throughout the structure, indicating a uniform distribution...
192
01:30Support Reactions
433
A coplanar force system refers to a set of forces that all lie in the same plane and are subject to different reactions between the point of contact and the supports. Understanding how different types of supports affect coplanar forces is crucial for designing safe and reliable structures that can withstand external loads.
The purpose of the supports is to prevent the translational motion of the system by applying an equal and opposite force and to prevent the system's rotation by applying...
The purpose of the supports is to prevent the translational motion of the system by applying an equal and opposite force and to prevent the system's rotation by applying...
433
01:19Net Torque Calculations
9.1K
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...
9.1K
01:17Factors Affecting Activity Coefficient
800
The extended Debye-Hückel equation indicates that the activity coefficient of an ion in an aqueous solution at 25°C depends on three partially interdependent properties: the ionic strength of the solution, the charge of the ion, and the ion size.
The activity coefficient value for an ion is close to one when the solution has almost zero ionic strength, i.e., when the solution shows close to ideal behavior. As the ionic strength of the solution increases from 0 to 0.1 mol/L, a...
The activity coefficient value for an ion is close to one when the solution has almost zero ionic strength, i.e., when the solution shows close to ideal behavior. As the ionic strength of the solution increases from 0 to 0.1 mol/L, a...
800
01:17Steady, Laminar Flow Between Parallel Plates
199
Understanding steady, laminar flow between parallel plates is essential for analyzing and designing flow in narrow rectangular channels, commonly found in various water conveyance and drainage systems. The Navier-Stokes equations govern fluid motion and are generally challenging to solve due to their nonlinearity. However, simplifications are possible in certain cases, like the steady laminar flow between parallel plates. For this scenario, we assume steady, incompressible, laminar flow.
199
00:57Power Expended by a Constant Force
7.6K
The relationship between work done and the time taken to do it can be explained using the concept of power. For example, several sprinters in a race may have the same velocity when they reach the finish line, therefore doing the same amount of work, but the winner does it in the least amount of time. Thus, power is defined as the rate of doing work. Since work can vary as a function of time, the average power is defined as the work done during a time interval, divided by the time interval.
7.6K