What is Biomechanics?

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What is Biomechanics?

• Biomechanics
• Hall. Basic biomechanics, p. 3
• ... application of mechanical principles to the
  study of living organisms. and use of the
  tools of mechanics . . . to study the anatomical
  and functional aspects of living organisms.
• Biomechanics of human movement
• Kreighbaum Barthels. Biomechanics A
  qualitative study of human movement , p 1
• that area of study wherein the knowledge and
  methods of mechanics are applied to the structure
  and function of the living human system.
• This course focuses on the biomechanics of human
  movement
• Good website on biomechanics Biomechanics world
  wide Home

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The Discipline of Kinesiology
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Various types/contexts of human movement
Occupational biomechanics
(Aging)
Sport biomechanics
Rehab biomech Orthopedic biom
Exercise biom?
Sport medicine?
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Branches of Sports Medicine
D discipline P profession
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P
D
D
?
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D
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D
P
P
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Selected practical problems that biomechanics can
help resolve

• Exercise biomechanics
• What is the most effective exercise for the
  abdominal muscles?
• Do you really need an abdominal exercise device?
  Which type is best?
• What types of exercises are effective in
  promoting bone density?
• Sport biomechanics
• What specific factors should a coach or athlete
  focus on in order to produce an increase in
  performance?
• Which mode of exercise is best for producing
  increased power performance?
• Which sport implement or exercise device is best
  suited for you?
• How does the height of the mound affect pitching
  technique and/or potential for injury?
• What movements and stresses contribute to carpal
  tunnel syndrome?
• Why do you really need an abdominal exercise
  device? Which type is best suited for you?

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Issues problems, contd

• Developmental/aging biomechanics
• Does exercise play a role in promoting bone
  density or preventing osteoporosis? How?
• Does activity level/type during formative years
  affect bone density later in life?
• How can we prevent falls in aging people?
• What special bone growth/injury problems do we
  have in youth? (mound height study)
• Occupational biomechanics (ergonomics)
• What movements and stresses contribute to carpal
  tunnel syndrome? Low back pain? Shoulder joint
  impingement?
• What is the most efficient, or effective way to
  do a particular work task?

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Problems issues, contd

• In what category does each belong?
• How can we prevent decreasing bone density in
  prolonged micro
• gravity environments?
• What is the effect of aging on skeletal muscle?
• Which type of tennis backhand is best -
  one-handed or two handed?
• What is the effect of testosterone
  supplementation on osteporosis?
• What is the effect of exercise on bone mineral
  content in pregnant women?
• What are the ground reaction forces during
  various types of aerobic dancing ? Which types
  are contraindicated for older women?
• Biomechanical assessment of knee arthroplasty
• Osteoporosis in paraplegics
• The scientific basis for closed-kinetic chain
  exercise after anterior cruciate ligament
  reconstruction

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General Approaches to Analyzing Biomechanics of
Human Movement

• Basic approaches to studying human movement
• Kinetic vs Kinematic
• Static vs Dynamic
• Qualitative vs Quantitative
• Maximize, minimize, or optimize
• Factors-Results Approach- a qualitative,
  heirarchial, deterministic model (Adrian, p 17)
• Identify result
• List factors that produce the result
• Holistic Principle Approach
• Describe the movement
• Describe overall performance goal in specific
  biomechanical terms
• Divide movement into phases
• Describe purpose/goal of each phase
• Identify anatomical, mechanical, and
  environmental considerations
• Determine biomechanical principles for successful
  performance of each phase and total movement
• Assess performance based on these principles

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Hays heirarchial factors-results analysis
model. Each lower factor influences the linked
factor above
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The Holistic Model The baseball swing
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Holistic Model the baseball swing
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Tools Needed for Biomechanical Analyses

• Prerequisite knowledge
• Mathematics
• Physics
• Anatomy
• Measurement tools
• Kinematics time, space relationships
• Kinetics forces (and their derivatives) and
  motion relationships
• Electromyography
• Problems, issues, and ideas

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Problems for Discussion Mon, Jan 31

• Straight-forward, formal quantitative problem
  involving simple kinematic equation
• Does the softball or baseball hitter have more
  time to react to a pitch? Assume that the
  baseball pitcher throws to home plate (60.5 ft,
  or 18.44 m from pitchers rubber) at a velocity
  of 90 mph (40 m/s) and the softball pitcher
  throws (46 ft, or 14.02 m from pitchers rubber)
  at a velocity of 60 mph (27 m/s).
• More general, complex quantitative problem
  involving both kinematics and kinetics
• A man fell from the railing of a walkway on a
  second-story apartment building. He was found
  lying unconscious on his back with his center of
  mass located 5 feet horizontally from a second
  story walkway and railing. The top of the
  railing was 21.6 ft above the ground. His blood
  alcohol content was found to be .30 (inebriated)
  and he has no memory of how he fell. In order
  to appraise liability for the accident, we need
  to determine if the victim walked into the
  railing or if he was sitting on the railing and
  fell off. Can this be done from the information
  given? How?

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Assignment for Monday, Jan 31

• Identify and be prepared to describe one or more
  areas of study or specific problems in
  biomechanics that you are most interested in,
  knowing more about, and/or perhaps do a
  literature review on
• Go to the Biomechanics world wide Home website
  and
• Locate a website that deals with problems and
  issues in an area of special interest to you
• Give a short verbal summary of the contents of
  the site to the class. Include in your comments
  the following (1) site URL and description,
  (2)general purpose, (3) intended audience, and
  (4) specifically, how the site is beneficial to
  you and others.
• Read (1) Hamill Ch 8 and 9 (Kinematics review)
  (2) Kreighbaum pp 537-555 Adrian pp 131-134,
  162-169