Part I prepares the reader with general knowledge about biomechanics and human anatomy. In order to have a better understanding of biome-chanics, the study of anatomy is extremely important.
The biomechanics of different sport branches have been described in many books. A prime example is track and field about which hundreds of films, scientific papers, and books have been written. The biomechanics of martial arts have not been investigated throughout. In this book, the reader can find questions and answers to many aspects related to mechan-ical laws adapted specifmechan-ically to martial arts.
In Part I, the author highlights different characteristics of the bone, joint, and muscles, such as composition, types, and functions. A major portion of Part I describes almost all body parts (musculoskeletal anatomy and their functions) and emphasizes different muscular regions, espe-cially the larger and stronger ones. Bones specifically are not described in this book, but as mentioned earlier in this book, the reader should consult basic anatomical books about bones.
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1
Introduction
1.1 WHAT IS BIOMECHANICS?
The application of forces to living organisms and the investigation of the effects of these forces on a human body or system, including forces that arise from within and outside of the body, is called biomechanics.
Biomechanics also includes the study of the structure and function of the biological system by the rule of mechanics applied to muscular activity.
Biomechanics is composed of two words, bios meaning “life” in Greek, and mechanics.
The term kinesiology, which is used interchangeably with biomechan-ics, is a combination of two Greek words, kinein meaning to “move” and logos meaning “to discourse.” A total meaning is “a discourse on move-ment,” and a definition of kinesiology is the study of muscles and body movement related to anatomy and mechanics.
The title “father of kinesiology” was given to the Greek philosopher Aristotle (384–322 bc), author of several treatises, including De Partibus Animalium (On the Parts of Animals) and De Motu Animalium (On the Movement of Animals), who described for the very first time the actions of the muscles and disposed them to geometric analysis. Another Greek mathematician and physicist, Archimedes (287–212 bc), developed hydro-static principles related to floating bodies that are still accepted as valid in fluid mechanics or the biomechanics of swimming.
A Roman citizen named Galen (ad 131–201) was considered to be the first physician for the gladiators. Galen wrote the essay De Motu Musculorum in which he described differences between motor and sensory nerves. He
described muscular tonus and introduced the terms diarthrosis and syn-arthrosis, which are still used to this day as the correct terminology in arthrology.
The great Leonardo da Vinci (1452–1519), an artist, engineer, and scientist, described the relationship between the center of gravity and body balance. He described the mechanics of standing, walking, and jumping.
Another Italian, Galileo Galilei (1564–1643), demonstrated that the accel-eration of a falling body is not proportionate to its weight and that the relationship of space, time, and velocity is the most important attribute in the study of motion.
Many other people such as Alfonso Borelli (1608–1679) stated that bones act as levers. Isaac Newton (1642–1727) established modern biomechanics and his laws of inertia, acceleration, and action–reaction are major and valid laws of modern biomechanics. We could mention perhaps hundreds of others who studied human anatomy and mechanics. These are just a few.
Biomechanists were concerned with integrating into their studies a number of different disciplines such as “structural–functional biome-chanics,” “exercise physiology,” and “motor behavior and control.”
1.2 IMPORTANCE OF BIOMECHANICS
Mechanics is a branch of physics and engineering that deals with the evaluation of forces responsible for maintaining an object or structure in a fixed position, as well as with the description, prediction, and causes of motion of an object or structure.
The importance of biomechanics for any physical educator is primary.
Biomechanics gives information and guidance about the function of the musculoskeletal system with respect to better technical solutions and adaptations to the related environment.
Biomechanics has to work in a tight relationship with exercise physiol-ogy. In order to understand the relationship between biomechanics and exercise physiology, here is an example: A marathon runner in order to be efficient in his running must know about leg stride (biomechanics) and the rhythm of breathing (physiology). Another example is taken from martial arts: a Judoka must know exactly every aspect of the Ukemi—breakfall techniques. By using the correct biomechanics, the Judoka can reduce the shock with the ground by approximately 80%.
Muscle contractions are guided by physiological functions and different forms of body movement, which again are related to biomechanics. Later on, detailed descriptions about muscular control of the human body will
be provided. In order to know the human potential of resistance against forces that arise from within or from outside of the body, it is important for physical educators to know about body types and especially about the composition of the bones, ligaments, and muscles. Knowing anatomical compositions and physiological functions, a good coach/instructor could avoid wrong executions and guide toward the correct biomechanical paths of certain technical executions.
An explanation is important to know about the difference between the basic knowledge of correct biomechanical executions and new (appar-ently incorrect biomechanical) technical executions. In this case, if the apparently incorrect biomechanical execution is more efficient versus the
“known correct technical execution,” then we speak about style. By the way, biomechanics dictate the correct technical executions, but style dictates new correct technical executions proved under stress of the competition.
1.3 BIOMECHANICS AND ITS DIVISION
Mechanics has two major fields: statics, which considers rigid bodies that are in a stable state of equilibrium, and dynamics, which studies objects that are in motion. Dynamics can be further divided into kinematics, which includes displacement, velocity, and acceleration without taking into con-sideration the forces acting on the body, and kinetics, which relates to the forces that cause motion associated with time and energy spent. Table 1.1 shows the area of study of biomechanics.
1.3.1 Statics
A kinematic chain is said to be in equilibrium when all the links of the chain are in balance. Equilibrium can be (a) stable, hanging, sitting, or standing position; (b) unstable, standing on one leg; and (c) neutral, a ball on the floor. For the maintenance of a stable/static position, there are important factors such as (1) center of gravity (CoG), (2) base of support (BoS), (3) height of CoG, (4) line of gravity, (5) mass of body, and others.
All these factors will be described later.
1.3.2 Dynamics
There are three general types of motion: rectilinear (translatory), angular (rotary), and curvilinear. In rectilinear motion, every particle of a body moves the same distance along a straight line parallel to the path of every other particle. The motion of the human body seldom uses rectilinear motion. When a boxer or karateka executes a straight jab, he does not
exhibit a complete rectilinear motion. At some point, the jab executions turn into rotary motion.
In angular motion, a body or a part of the body rotates around an axis.
The body or the body part travels with the same direction, angle, and time.
In curvilinear motion, the body follows a curved path.
TABLE 1.1 Biomechanics and Its Division Biomechanics
Mechanical area
Solids
• Deformable body’s
• Elastic
• Plastic
• Strength of materials
Rigid
body’s Watery Viscous Kinetics Kinematics
Statics Dynamics Fluids Biological
area
Anatomical
factors Physiological factors
Bone, tendon, ligament, cartilage, muscle
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