Q.
Answer
Gait analysis is the systematic study of animal locomotion, more specific as a study of human motion, using the eye and the brain of observers, augmented by instrumentation for measuring body movements, body mechanics, and the activity of the muscles. Gait analysis is used to assess, plan, and treat individuals with conditions affecting their ability to walk. It is also commonly used in sports biomechanics to help athletes run more efficiently and to identify posture-related or movement-related problems in people with injuries.
The study encompasses quantification, i.e. introduction and analysis of measurable parameters of gaits, as well as interpretation, i.e. drawing various conclusions about the animal (health, age, size, weight, speed, etc.) from its gait.
Gait analysis commonly involves the measurement of the movement of the body in space (kinematics) and the forces involved in producing these movements (kinetics).
A typical modern gait lab has several to many cameras (video and/or infrared) placed around a walkway or treadmill, which are linked to a computer. The patient has single markers applied to anatomical landmarks, such as palpable bony landmarks (e.g., the iliac spines of the pelvis, the malleoli of the ankle, and the condyles of the knee), or clusters of markers applied to the middle of body segments. The patient walks down the walkway or the treadmill and the computer calculates the trajectory of each marker in three dimensions. A model is applied to compute the underlying motion of the bones. This gives a full breakdown of the motion at each joint.
In addition, to calculate movement kinetics, most laboratories have floor-mounted load transducers, also known as force platforms, which measure the ground reaction forces, including magnitude, direction, and location (called centre of pressure). Adding this to the known dynamics of each body segment, enables the solution of equations based on the NewtonâEuler equations of motion permitting computations of the net forces and the net moments of force about each joint at every stage of the gait cycle. The computational method for this is known as inverse dynamics.
This use of kinetics, however, does not result in information for individual muscles but muscle groups, such as the extensor or flexors of the limb. To detect the activity and contribution of individual muscles to movement, it is necessary to investigate the electrical activity of muscles. Many labs also use surface electrodes attached to the skin to detect the electrical activity or electromyogram (EMG) of, for example, a muscles of the leg. In this way it is possible to investigate the activation times of muscles and, to some degree, the magnitude of their activationâthereby assessing their contribution to gait. Deviations from normal kinematic, kinetic, or EMG patterns are used to diagnose specific conditions, predict the outcome of treatments, or determine the effectiveness of training programs.
Medical diagnostics: Pathological gait may reflect compensations for underlying pathologies, or be responsible for causation of symptoms in itself. The study of gait allows these diagnoses to be made, as well as permitting future developments in rehabilitation engineering. Aside from clinical applications, gait analysis is widely used in professional sports training to optimise and improve athletic performance.
Biometric identification and forensics: Gait analysis techniques allow for the assessment of gait disorders and the effects of corrective Orthopedic surgery. Options for treatment of cerebral palsy include the paralysis of spastic muscles using Botox or the lengthening, re-attachment or detachment of particular tendons. Corrections of distorted bony anatomy are also undertaken. It is heavily used in the assessment of sports and investigations into the movement of a large variety of other animals.
http://en.wikipedia.org/wiki/Gait_analysis
Gait analysis is the systematic study of animal locomotion, more specific as a study of human motion, using the eye and the brain of observers, augmented by instrumentation for measuring body movements, body mechanics, and the activity of the muscles. Gait analysis is used to assess, plan, and treat individuals with conditions affecting their ability to walk. It is also commonly used in sports biomechanics to help athletes run more efficiently and to identify posture-related or movement-related problems in people with injuries.
The study encompasses quantification, i.e. introduction and analysis of measurable parameters of gaits, as well as interpretation, i.e. drawing various conclusions about the animal (health, age, size, weight, speed, etc.) from its gait.
Gait analysis commonly involves the measurement of the movement of the body in space (kinematics) and the forces involved in producing these movements (kinetics).
A typical modern gait lab has several to many cameras (video and/or infrared) placed around a walkway or treadmill, which are linked to a computer. The patient has single markers applied to anatomical landmarks, such as palpable bony landmarks (e.g., the iliac spines of the pelvis, the malleoli of the ankle, and the condyles of the knee), or clusters of markers applied to the middle of body segments. The patient walks down the walkway or the treadmill and the computer calculates the trajectory of each marker in three dimensions. A model is applied to compute the underlying motion of the bones. This gives a full breakdown of the motion at each joint.
In addition, to calculate movement kinetics, most laboratories have floor-mounted load transducers, also known as force platforms, which measure the ground reaction forces, including magnitude, direction, and location (called centre of pressure). Adding this to the known dynamics of each body segment, enables the solution of equations based on the NewtonâEuler equations of motion permitting computations of the net forces and the net moments of force about each joint at every stage of the gait cycle. The computational method for this is known as inverse dynamics.
This use of kinetics, however, does not result in information for individual muscles but muscle groups, such as the extensor or flexors of the limb. To detect the activity and contribution of individual muscles to movement, it is necessary to investigate the electrical activity of muscles. Many labs also use surface electrodes attached to the skin to detect the electrical activity or electromyogram (EMG) of, for example, a muscles of the leg. In this way it is possible to investigate the activation times of muscles and, to some degree, the magnitude of their activationâthereby assessing their contribution to gait. Deviations from normal kinematic, kinetic, or EMG patterns are used to diagnose specific conditions, predict the outcome of treatments, or determine the effectiveness of training programs.
Medical diagnostics: Pathological gait may reflect compensations for underlying pathologies, or be responsible for causation of symptoms in itself. The study of gait allows these diagnoses to be made, as well as permitting future developments in rehabilitation engineering. Aside from clinical applications, gait analysis is widely used in professional sports training to optimise and improve athletic performance.
Biometric identification and forensics: Gait analysis techniques allow for the assessment of gait disorders and the effects of corrective Orthopedic surgery. Options for treatment of cerebral palsy include the paralysis of spastic muscles using Botox or the lengthening, re-attachment or detachment of particular tendons. Corrections of distorted bony anatomy are also undertaken. It is heavily used in the assessment of sports and investigations into the movement of a large variety of other animals.
http://en.wikipedia.org/wiki/Gait_analysis
would the Flip MinoHD 120-Minute be good to record sports?
I'm a hurdler and i want people to record my track races and i was wondering if this would be a good camera to video tape with.
Answer
no, not if you intend to slow down the video for precise motion analysis. no HD format works for that because they all use Group of Frames architecture. AVCHD for example uses a frame rate of 4 fps for recording, and then on playback it interpolates to reproduce the missing frames. A lot can happen in a 1/4 second that will be entirely missed or falsely interpolated on playback. A better choice would be miniDV. DV takes 60 fields per second, each field is a unique full picture and you can move frame to frame with no missing motion details.
no, not if you intend to slow down the video for precise motion analysis. no HD format works for that because they all use Group of Frames architecture. AVCHD for example uses a frame rate of 4 fps for recording, and then on playback it interpolates to reproduce the missing frames. A lot can happen in a 1/4 second that will be entirely missed or falsely interpolated on playback. A better choice would be miniDV. DV takes 60 fields per second, each field is a unique full picture and you can move frame to frame with no missing motion details.
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