Related Experiment Video
Updated: Apr 24, 2026
08:55
Determining and Controlling External Power Output During Regular Handrim Wheelchair Propulsion
Published on: February 5, 2020
7.5K
Forces and mechanical energy fluctuations during diagonal stride roller skiing; running on wheels?
Alyse L Kehler1, Eliska Hajkova2, Hans-Christer Holmberg3
1Department of Integrative Physiology, University of Colorado, Boulder, CO 80309, USA alyse.kehler@gmail.com.
The Journal of Experimental Biology
|September 6, 2014
Summary
Diagonal stride roller skiing does not conserve mechanical energy like running. Unlike walking, it shows in-phase energy fluctuations, but lacks elastic energy storage, making it biomechanically unique.
Area of Science:
- Biomechanics
- Human locomotion
- Sports science
Background:
- Terrestrial locomotion conserves mechanical energy via inverted pendulum (walking) and spring-mass (running) mechanisms.
- Diagonal stride cross-country skiing (DIA) superficially resembles running, prompting investigation into shared energy conservation principles.
Purpose of the Study:
- To investigate if diagonal stride roller skiing (DIA) utilizes similar spring-mass mechanisms as running for mechanical energy conservation.
- To compare the phase relationships and magnitudes of kinetic energy (KE) and gravitational potential energy (GPE) fluctuations between walking, running, and DIA.
Main Methods:
- Experienced skiers (N=9) performed walking, running, and DIA on a level dual-belt treadmill at controlled speeds.
- Perpendicular and parallel ground reaction forces were recorded to calculate the center of mass's KE and GPE.
- Phase relationships between KE and GPE fluctuations were analyzed for each locomotion type.
Main Results:
- Walking exhibited out-of-phase KE and GPE fluctuations, consistent with the inverted pendulum mechanism.
- Running and DIA showed in-phase KE and GPE fluctuations.
- Unlike running, DIA dissipated KE as heat during the glide phase, preventing elastic energy storage and return.
Conclusions:
- Diagonal stride cross-country skiing (DIA) does not function as a spring-mass system like running.
- The in-phase energy fluctuations observed in DIA are superficial, as elastic energy storage and return are absent.
- DIA is a biomechanically distinct form of locomotion, differing significantly from both walking and running.
Related Concept Videos
01:10Energy Diagrams - II
11.1K
Energy diagrams are important to understand the dynamics of a system. The topology of an energy diagram helps illustrate the equilibrium points of the system.
The point in the energy diagram at which the system’s potential energy is the lowest is known as the local minima. The system tends to stay in this position indefinitely unless acted upon by a net force. The slope of the potential energy diagram at the local minima is zero, indicating that zero net force is acting on the system. The...
The point in the energy diagram at which the system’s potential energy is the lowest is known as the local minima. The system tends to stay in this position indefinitely unless acted upon by a net force. The slope of the potential energy diagram at the local minima is zero, indicating that zero net force is acting on the system. The...
11.1K
01:16Equation of Motion: General Plane motion - Problem Solving
620
Consider a lawn roller with a mass of 100 kg, a radius of 0.2 meters, and a radius of gyration of 0.15 meters. A force of 200 N is applied to this roller, angled at 60 degrees from the horizontal plane. What will be the angular acceleration of the lawn roller?
The friction between the roller and the ground is characterized by two coefficients. The static friction coefficient is 0.15, while the kinetic friction coefficient is 0.1. These values are crucial in understanding the interaction between...
The friction between the roller and the ground is characterized by two coefficients. The static friction coefficient is 0.15, while the kinetic friction coefficient is 0.1. These values are crucial in understanding the interaction between...
620
01:14Energy Diagrams - I
4.2K
The dynamics of a mechanical system can be easily understood by interpreting a potential energy diagram. Since energy is a scalar quantity, the interpretation of the dynamics of the system becomes even simpler.
Take the example of a skater on a parabolic ramp. The potential energy at different points along the ramp will be proportional to the height of the ramp, which varies quadratically with the horizontal position on the ramp. As the skater moves down the ramp from the highest position,...
Take the example of a skater on a parabolic ramp. The potential energy at different points along the ramp will be proportional to the height of the ramp, which varies quadratically with the horizontal position on the ramp. As the skater moves down the ramp from the highest position,...
4.2K
01:05Static and Kinetic Frictional Force
20.4K
One of the simpler characteristics of sliding friction is that it is parallel to the contact surfaces between systems, and is always in a direction that opposes the motion or attempted motion of the systems relative to each other. If two systems are in contact and moving relative to one another, then the friction between them is called kinetic friction. For example, kinetic friction slows a hockey puck sliding on ice.
However, if two systems are in contact and are stationary relative to one...
However, if two systems are in contact and are stationary relative to one...
20.4K
01:17Rolling Resistance: Problem Solving
984
Rolling resistance, also known as rolling friction, is the force that resists the motion of a rolling object, such as a wheel, tire, or ball, when it moves over a surface. It is caused by the deformation of the object and the surface in contact with each other, as well as other factors like internal friction, hysteresis, and energy losses within the materials. Rolling resistance opposes the object's motion, requiring additional energy to overcome it and maintain movement. In practical...
984
01:09Rolling Without Slipping
4.3K
People have observed the rolling motion without slipping ever since the invention of the wheel. For example, one can look at the interaction between a car's tires and the surface of the road. If the driver presses the accelerator to the floor so that the tires spin without the car moving forward, there must be kinetic friction between the wheels and the road's surface. If the driver slowly presses the accelerator, causing the car to move forward, the tires roll without slipping. It is...
4.3K