Related Experiment Video
Updated: May 24, 2026
08:55
Determining and Controlling External Power Output During Regular Handrim Wheelchair Propulsion
Published on: February 5, 2020
Reliability of power output during eccentric sprint cycling
Matt Brughelli1, Marc Van Leemputte
1Department of Biomedical Kinesiology, Faculty of Kinesiology and Rehabilitation Sciences, KU Leuven, Leuven, Belgium.
Journal of Strength and Conditioning Research
|February 21, 2012
Summary
Eccentric sprint cycling power output is reliable for physically active males after two familiarization sessions at cadences between 60-120 rpm. Avoid 40 rpm due to poor reliability.
Area of Science:
- Sports Science
- Exercise Physiology
- Biomechanics
Background:
- Eccentric exercise is crucial for muscle strength and injury prevention.
- Isokinetic dynamometry is a standard tool for assessing muscle function.
- Reliability of eccentric cycling power metrics requires further investigation.
Purpose of the Study:
- To assess the reliability of power outputs during maximal intensity eccentric cycling sprints.
- To determine optimal cadences for reliable eccentric sprint cycling measurements.
Main Methods:
- Fourteen physically active males completed 6-second eccentric cycling sprints at 40, 60, 80, 100, and 120 rpm over four sessions.
- Mean power (MP) and peak power (PP) were recorded.
- Reliability was analyzed using coefficient of variation (CV) and intraclass correlation coefficient (ICC).
Main Results:
- Power outputs (MP and PP) showed significant increases from the first to subsequent trials, with no significant differences from trial 2 onwards.
- Reliability (CV <10%, ICC >0.90) was established for cadences of 60-120 rpm between trials 3 and 4.
- The 40 rpm cadence demonstrated unacceptable reliability (CV and ICC) throughout all trials.
Conclusions:
- Eccentric sprint cycling demonstrates reliable power output measurements at cadences from 60 to 120 rpm after two familiarization sessions.
- The 40 rpm cadence should be avoided for reliable eccentric cycling power assessments.
- This study provides valuable insights for researchers and coaches utilizing eccentric cycling protocols.
Related Concept Videos
01:16Eccentric Loading
Eccentric loading is a crucial concept in the study of structural engineering and mechanics, particularly when analyzing the stability and stress distribution in columns. Unlike centric loading, where the force is applied along the centroidal axis, causing uniform compression, eccentric loading occurs when a force is applied off-center. This off-center application introduces not only direct compressive stress but also bending stress, significantly influencing the column's behavior under load.
01:22Muscle Stimulation Frequency
The contraction strength of muscles is regulated by motor neurons, which modulate the frequency of action potentials dispatched to the motor units based on the body's requirements. This process of varying the muscle stimulation frequency allows muscles to contract with a force that is precisely tailored to the needs of the moment, whether lifting a feather or a heavy box.
Wave summation
At low firing rates, motor neurons induce individual twitch contractions in muscle fibers. These twitches...
Wave summation
At low firing rates, motor neurons induce individual twitch contractions in muscle fibers. These twitches...
01:25Energy Supply for Muscle Contraction
Skeletal muscle fibers have the unique ability to switch between rest and contraction states, using different sources of ATP for energy. The contraction cycle and Ca2+ transport back into the sarcoplasmic reticulum for relaxation require significant ATP. However, the ATP reserves in muscle fibers are limited and can only sustain contractions for a few seconds. Additional ATP production becomes necessary for prolonged contractions. As a result, muscle fibers generate ATP through various sources,...
01:26Carnot Cycle and Efficiency
The Second Law of Thermodynamics asserts that it's impossible for any heat engine to achieve 100% efficiency. While contemplating the maximum possible efficiency, Nicolas Sadi Carnot conceptualized an ideal heat engine. This engine gets its energy from a high-temperature reservoir. It then performs some work and releases the remaining energy into a low-temperature reservoir.The Carnot cycle, named after Sadi Carnot, is fully reversible. The cycle consists of four distinct stages. In the first...
01:08Power
The concept of work involves force and displacement; meanwhile, the work-energy theorem relates the net work done on a body to the difference in its kinetic energy, calculated between two points on its trajectory. While none of these quantities or relations involves time explicitly, we know that the time available to accomplish work is often just as important as the amount of work itself. For example, sprinters in a race may have achieved the same velocity at the finish, therefore,...