In my previous post, I started with an introduction to Biomechanics covering the basics or force, exercise and how to implement optimum training. In this article, we will finish off the introduction by covering the basic principals of mechanics, kinematics, kinetics and the principles of structure and function.
Feel free to head back to part 1 of this introduction at: @run.vince.run/an-introduction-to-biomechanics-part-1
Basic Principles in Mechanics
There are three fundamental units of mechanics. These are Time, Distance and Mass. There are generally two ways to measure these units, Quantitive which involves numbers and Qualitative measurements that involve nonnumeric descriptions of quality.
Foundations of Functional and Sports
Biomechanics are primarily based on the branch of mechanics known as Rigid-Body Mechanics. Within Rigid-Body Mechanics, it includes both Statics and Dynamics, where Statics is the study of systems in constant motion. This is the study of Newton's first law which is the law of inertia, where Momentum is equal to Motion.
Dynamics is the study of systems in which acceleration is present and covers Newton's second law, which is the law of Acceleration.
Kinematics and Kinetics
The definition of Kinematics is the description of motion and movement with no regards to forces The definition of Kinetics is study of the actions of forces associated with motion.
Biomechanics allows us to determine the correct exercise and correct technique for the individual. Biomechanics allows us to answer the question “What’s happening in this exercise/sport/drill and how can we make it better?” Biomechanics explains why adaptations happen and then determine a course of action.
In explaining the physiological adaptations to the stress of exercise, first there is either good stress or bad stress(neuromuscular). The structural effects that will result in hypertrophy or growth. Functional effects will result in inter-muscular coordination, intramuscular coordination and reflexive changes.
Wolff's Law: the densities, and to a lesser extent, the sizes and shapes of bones are determined by the magnitude and direction of the acting forced
Davis' Law: is used in anatomy to describe how soft tissue when placed under unremitting tension, elongate by the addition of new material. When remaining uninterrupted in a lax state, they gradually shorten by the absorption of material.
Principles of Structure and Function
The design of a joint is determined by its function and the nature of its components
Once a joint is constructed, the structure of the joint will determine its function. Joints that serve a single function are less complex than joints that serve multiple functions
Putting it all Together in Biomechanics we:
Analyze movement to Optimize the movement in order to Maximize performance and Minimize injury. In other words we customise the exercise for each individual and look at the forces, load the joint and to then fire the muscle correctly.
When Analyzing, will look at the kinematics (or the actual movement), Linear and Angular Human Movement Kinematics include Linear and Angular. You will need to look at Osteokinematics, which is bone movement and Arthrokinematics, which is joint movement.
To Optimise, we need to look at the capabilities, goals needs and does the exercise make sense for the wants, goals and needs of the athlete. To Maximise performance, we need to look at mechanical and physiological efficiency and possibly alter the technique to make the athlete more efficient.
Finally, to Minimise the chance of injury, we need to understanding the stress and force being placed on the body. Elastic force means it will bounce back to the original shape, plastic means it will not and may eventually break and Yeild strength is when it moves from elastic to plastic.
"The same forces that move and stabilise the body also have the potential to deform and injure the body."
Donald A Neumann PT PhD
Exercise can be looked as physical stress placed on the body’s structure to which the body will adapt. All physiological effects of exercise (good and bad) are directly due to the mechanical stress placed on the body. I order to improve performance and reduce injury, first must understand how to analyse and optimise Biomechanics.
So a lot to it for just an introduction and hopefully I will be able to remember this all and not confuse myself.
About The Author
I am a DevOps Engineer, Endurance Athlete, Biomechanics Student and Author. We can all achieve amazing things, it's just a matter of trying, I want to change the world, one run at a time.