Biomechanics

2. Biomechanics – What is it?
໘ The term biomechanics combines
 The prefix bio, meaning “life,”
 With the field of mechanics,
໘ Which is the study of the actions of forces.
‣ “Mechanics” is a branch of physics that is concerned with the
motion and deformation of bodies that are acted on by mechanical
disturbances called forces.
໘ The study of the structure and function of biological systems by
means of the methods of mechanics.
໘ The science concerned with the internal and external forces acting
on the human body and the effects produced by these forces.

3. Mechanics
Bio
Biomechanics – ?
Biomechanics is the application of the principles of mechanics to the systems
of the human body. In biomechanics, we study the forces of nature acting on
the human body when a person picks up an object, walks or stands still.

4. Kinesiology – Is it the same as biomechanics?
⇨ Kinesis (motion) + -logy (science, study of)
Applied anatomy and mechanics
⇨ Kinesiology = anatomy (science of structure) + physiology
(science of body function) + mechanics (science of
movement) = science of movement of the human body.
⇨ The living organism most commonly of interest is the
human body.

5. ֍
⁌ First- kinesiology as the scientific study of human movement
can be an general term used to describe any form of
anatomical, physiologic, psychological, or mechanical human
movement evaluation.
⁌ Second- kinesiology describes the content of a class in which
human movement is evaluated by examination of its source
and characteristics.
☞ Biomechanists use the tools of mechanics, to study the
anatomical and functional aspects of living organisms .
☞ Anthropometric:- the term which related to the dimensions
and weights of body segments.

6. Biomechanics:
Does it exist in more
than one field?
Exercise and sport biomechanics
Orthopedic biomechanics
Occupational biomechanics
Biomechanics of other biological systems

7. Biomechanics: Does it exist in more
than one field?
Exercise and sport biomechanics
→ improving athletic performance, reduction of athletic injuries

8. Biomechanics: Does it exist in more
than one field?
Orthopedic biomechanics
→ Artificial limbs, joints, and orthoses to improve functional
movement capacity
→ Study of natural and artificial biological tissues

9. Biomechanics: Does it exist in more
than one field?
Occupational Biomechanics
→ Ergonomics and Human Factors
→ reduction of workplace injuries

10. Biomechanics: Does it exist in more
than one field?
Biomechanics of other biological systems
→ Comparative biomechanics (e.g., swimming in fish, locomotion in
apes)
→ Equine (horse) and canine (dog) racing performance

13. ₰ Statics and dynamics are two major sub-branches of mechanics.
☞ Statics is the study of systems that are in a state of constant
motion, that is
 either at rest (with no motion)
 or moving with a constant velocity.
☞ Dynamics is the study of systems in which acceleration is
present.
 Kinematics and kinetics are further subdivisions of
biomechanical study.

14.  The kinematics of the movement is
 What we are able to observe visually when watching a body in motion
 Involves the study of
 The size,
 Sequencing,
 Timing of movement,
 Without reference to the forces that cause or result from the motion.
 Kinetics is
 The study of the forces associated with motion.

15. ₰ Biomechanists may have academic backgrounds in
 Zoology;
 Orthopedic,
 Cardiac, or sports medicine;
 Biomedical or biomechanical engineering; physical therapy;
 or kinesiology,
₰ Biomechanics is also a scientific branch of sports medicine.
 Sports medicine is an umbrella term that encompasses both
clinical and scientific aspects of exercise and sport.

16. ₰ The effects of microgravity on the human musculoskeletal
system.
₰ Of concern is the fact that astronauts who have been out
of the earth’s gravitational field for just a few days have
returned with
© muscle atrophy,
© cardiovascular and immune system changes,
© and reduced bone density, mineralization, and strength,
especially in the lower extremities
₰ Another approach involves combining voluntary muscle
contraction with electrical stimulation of the muscles to
maintain muscle mass and tone.

17. ₰ Sport biomechanists have also directed efforts at improving the
biomechanical, or technique, components of athletic performance.
₰ Study of baseball pitchers has determined that high-velocity
pitchers display
• greater external rotation at the shoulder,
• more forward trunk tilt at ball release,
• higher-extension angular velocity at the lead knee,
• and greater angular velocity of the pelvis and upper torso
than lower-velocity pitchers

18. ₰ The case of four-time Olympic discus champion Al Oerter
 These factors include the following:
• The speed of the discus when it is released by the thrower
• The projection angle at which the discus is released
• The height above the ground at which the discus is released
• The angle of attack (the orientation of the discus relative to the
prevailing air current).
₰ High-speed cameras
• can record performances in great detail, and when the film or video is
analyzed, the actual projection height, velocity, and angle of attack
can be compared to the computer-generated values required for
optimal performance.

19. ₰ Other concerns of sport biomechanists relate to
☞ minimizing sport injuries
 through both identifying dangerous practices
 and designing safe equipment and apparel
₰ In recreational runners, for example, research shows that
☞ The most serious risk factors for overuse injuries are
training errors such as
 a sudden increase in running distance or intensity,
 excess cumulative mileage,
 and running on cambered surfaces

20. ₰ An added complication is that equipment designed to protect
one part of the body may actually contribute to the likelihood of
injury in another part of the musculoskeletal system.
 Modern ski boots and bindings,
 While effective in protecting the ankle and lower leg
against injury,
 Unfortunately contribute to severe bending moments at
the knee when the skier loses balance.
₰ An area of biomechanics research with implications for both
 Safety
 and performance is sport shoe design

21. Quantitative versus Qualitative Problems
໘ Analysis of human movement may be either
 Quantitative
 or Qualitative
☞ Quantitative implies that numbers are involved,
☞ Qualitative refers to a description of quality without the use
of numbers

23. The END