ch 9: biomechanics

what is biomechanics?

study of human body in motion

what does biomechanics involve?

anatomy, motor control, physics, exercise physiology, and engineering

kinesiology vs biomechanics?

Kinesiology is the parent discipline of biomechanics focusing on the overall study of human movement, whereas biomechanics specifically focuses on the motions and mechanical forces involved in movement

Biomechanics can be traced back to the:

Greeks

Biomechanics early influences

Aristotle examined complex movements like running and walking, and Archimedes studied floating bodies and their movement in water

biomechanics renaissance advances

Leonardo da Vinci explored human anatomy in motion. Galileo Galilei studied falling bodies, laying the groundwork for mechanical movement analysis. Alfonso Borelli wrote the first biomechanical "textbook," De Motu Animalium

Fundamental Laws of biomechanics

Isaac Newton developed his mechanical laws, which are foundational to biomechanics, and also invented calculus, statics, and dynamics

Biomechanics 19th Century Progress

This century saw the foundation of electromyography and the development of techniques for measuring movement kinematics and kinetics. Key figures include the Weber brothers, Eadweard Muybridge (cinematography of motion), and Étienne Jules Marey (photographic movement analysis)

Biomechanics 20th Century Emergence as a Discipline

Biomechanics became an academic field with graduate programs. Richard Nelson established the first biomechanics research laboratory in the US in 1966

Key Organizations and Publications of biomechanics

The Journal of Biomechanics originated in 1968. The International Society of Biomechanics (ISB) was founded in 1973, and the American Society of Biomechanics in 1976

Modern Biomechanics

Characterized by accelerated technological innovation (activity monitors, wearables, robotics) and dedicated research facilities like the Biomechanics Research Building at the University of Nebraska at Omaha (completed in 2013) and the establishment of Biomechanics departments offering degree programs

areas of study in biomechanics

• Developmental biomechanics

• Biomechanics of exercise and sports

• Rehabilitative biomechanics

• Occupational biomechanics

• Forensic biomechanics

developmental biomechanics

evaluates essential movement patterns across the live span; allows for comparison of an individual’s performance with overall patterns to determine level of ability (ex: therapies for children with developmental disorders)

biomechanics of exercise and sport

focuses on postures and movement patterns to minimize risk of injury and improve performance. (ex: helps to design footwear and exercise equipment, development and test protective devices, analyze golf swings)

force platform

measures the force between the shoe and the ground; can be measured in 3 directions (X,Y and Z)

rehabilitative biomechanics

studies the movement patterns of people who have been injured or disabled; helps develop appropriate rehabilitative protocols (ex: studying effects of peripheral arterial disease on gait patterns, determine specific gait impairments and developing rehab techniques)

occupational biomechanics

focuses on providing a safer and more efficient environment for workers (ex: developing better safety equipment, develop safer or more mechanically efficient tools)

forensic biomechanics

focuses on questions that arise in legal situations; provides forensic investigations, technical reports, and expert testimony in human performance-related incidents involving personal injury (ex: possible causes of a fall; potential effects of seat belts/shoulder harness on spinal injuries during a car accident)

motion recording devices

captures body motion with the use of optical lenses; can be evaluated with more precision than the naked eye alone

cinematography, videography and photography

key motion and image recording techniques in biomechanics; Historically, high-speed cinematography studied fast movements. Now, videography and digital imaging allow instant analysis of kinematics

magnetic resonance imaging (MRI) (Biomechanics)

A noninvasive technology using strong magnetic fields for detailed body images. It helps evaluate injuries, study muscle changes after training, assess body composition, and investigate muscle activation patterns during movement

Goniometers

provide kinematic data on joint positioning; used to measure static positions of limb segments with respect to joint axis

dynamography

provides kinetic or force data

pressure insole

example of a dynamographic device

accelerometer

electronic device measuring acceleration forces; can provide information about the forces in outdoor or workplace environments

electromyograph

records electrical changes that occur in a muscle before, during or after contaction

modeling and stimulation

provide prediction of kinematic and kinetic data; used to provide insight into specific activities or events

instrumented staircase

can accurately measure the amount of force applied on each step during stair ascent and descent and can detect the usage of handrails during stair negotiation.

instrumented treadmill

used to measure amount of force applied while walking or running on the treadmill

computerized dynamic posturography

used to measure the control of posture and balance in upright stance

educational preparations for biomechanics?

typically people obtain a higher degree such as a masters or phd

Biomechanics is the study of the human body in motion. If you are studying the effects of a barbell squat on muscle adaptation, which measuring tool will you use?

EMG

Schieber, M.N. et al. ascertained that peripheral arterial disease not only causes pain, but also:

gait dysfunction

Researchers studied the effects of dynamic balance of transtibial amputees changing after a three week adaptation period on a new prosthetic foot. What measurement tool did researchers use to measure subjects' movement?

motion recording device

The nineteenth century contributions to biomechanics had made great strides. Who and what was a significant event in 1931?

W.O. Fenn and his analysis of sprint running

In the 1970s the design of footwear changed due to biomechanics with the goal to improve performance and reduce injury. Hébert-Loiser et al. major finding was that Nike Vapor Max 4 improved:

running economy

Multiple sclerosis is another population that can benefit from rehabilitative biomechanics?

true

Biomechanists provide forensic investigations. For example, what would they investigate in a homicide incident?

aspects related to how the victim’s injuries were sustained

This measurement tool would be best used to study human natural locomotion

instrumented treadmill

Which human movement research method takes biomechanics outside of the laboratory?

accelerometer, head mounted displays