Viewing the Human Body as the Ultimate Machine

Viewing the Human Body as the Ultimate Machine

Excerpt from chapter two of the Powerlifting Specialist Course.

Tom Delong education director

The NCCPT is committed to ensuring everyone seeking our certification are well educated in the foundational sciences related to the movement sciences. One of our missions to ensure those involved in physical training program development are equipped with the right tools necessary for analyzing movement, optimizing technique for all participants, maximizing the instruction process for all exercises to maximum effectiveness which will, in turn, help minimize the risk of injury. Another mission is to assess the vast amount of training information then teach how to use this information accordingly and properly. This information should be logically organized to ensure all the pieces of this information fit together correctly for optimizing its usage for success. Below is a pictorial description to give one an idea of how random information, properly linked together, will form one’s ability to develop “knowledge.”


Today’s access to the World Wide Web (www) has saturated the internet with an over-abundance of information. While this instantaneous access to so much information can be extremely useful, the major drawback to this endless stream of usable information can be misleading. The easy access to all this material is a “pro”; the “con” is anyone can post what is presumably the most correct and/or “state of the art” and “advanced scientific” evidence (and we use the term “evidence” cautiously) based on opinion (anecdotal) and not actually empirical evidence (true research). The message of the above diagram is to review all the information one can find related to strength training then connect this information together logically and scientifically to see

what is optimal for the individual needing this information. Our message is all the information available may be useful if one analyzes this information logically, experiments with the information deemed most compatible/valid, then optimizes/utilizes this usable information accordingly to reach said goal(s). One’s training education begins with describing the human machine, what it is made of, how it is constructed, and how it functions properly.


To begin, all trainers must learn to view the human body as a living machine. People as a whole do not view our body in this sense, however, if we look at the intricacies of our bodies, one will begin to see the amazing complexities of this well-designed machine.

Description of a Machine

A machine is a structure or mechanism consisting of one or more parts that uses energy to meet a particular goal. Machines are usually powered by mechanical, chemical, thermal, or electrical means, and are often motorized. A simple machine is a device that simply transforms the direction or magnitude of a force (a force is anything that causes or tends to cause a change

in motion or is any influence that causes a free body to undergo acceleration), but a large number of more complex machines exist. Examples of complex ma- chines include vehicles, electronic systems, molecular machines, computers, smart phones, and all communication systems (television, radio, and, as previously mentioned, the world-wide web or internet).

Historically, the word machine derives from the Latin word machina, which in turn derives from the Greek (Doric μαχανά makhana, Ionic μηχανή mekhane “contrivance, machine, engine”, a derivation from μῆχος mekhos “means, expedient, remedy”). A wider meaning of “fabric, structure” is found in classical Latin, but not in Greek usage. This meaning is found in late medieval French, and is adopted from the French into English

in the mid-16th century. In the 17th century, the word could also mean a scheme or plot, a meaning now ex- pressed by the derived machination. The modern mean- ing develops out of specialized application of the term to stage engines used in theater and to military siege engines, both in the late 16th and early 17th centuries. The OED traces the formal, modern meaning to John Harris’ Lexicon Technicum (1704), which states: Machine, or Engine, in Mechanicks, is whatsoever hath Force sufficient either to raise or stop the Motion of a Body… Simple Machines are commonly reckoned to be six in number, viz. the Ballance, Leaver, Pulley, Wheel, Wedge, and Screw… Compound Machines, or Engines, are innumerable.

The word engine used as a (near-) synonym both by Harris and in later language derives ultimately (via Old French) from Latin ingenium “ingenuity, an invention.” The types of machines we utilize are numerous. Categories of machines include:

    • Simple (levers, pulleys)
    • Electrical (including electronics and computers) Molecular

Within each machine are elements (also called “parts”). These elements include mechanisms and controllers. Mechanisms control movement in various ways (gears, joints, and particularly linkage systems with specific joint configurations). Controllers combine sensors, logic, and actuators to maintain the performance of compo- nents of a machine. In many machines there are devices such as a thermostat i.e. as the temperature increas-

es the thermostat will active a device to open a valve to allow cooling water to increase accordingly as the speed of the machine increases (automatic control system) These mechanical systems can be controlled by a programmable computer to control and monitor all the machine’s system as well as programmed with specific instructions to allow movement in a specific fashion.

These directions from the programs allow servo motors to accurately position a shaft/linkage in response to an

electrical command much like the actuators that make robotic systems possible.

So how does this information relate to physical training

i.e. exercise? The answer – EVERYTHING! The human body is considered one of the most elaborate and amazing machines ever designed. As previously stated, a machine is a structure consisting of one or more parts that uses energy to meet a particular goal. The zhuman body consists of one or more parts and uses energy to meet a particular goal as well. Machines are usually powered by mechanical, chemical, thermal, or electrical means, and are often motorized. The human body is a combination of and powered by the same concepts/mechanisms utilized by man-made machines

i.e. computer (brain), electrical (nervous system), chem- ical (digestive system), thermal (endocrine system), and mechanical (kinetic chain) to monitor and control every system in the body to include the systems that cause and control motion.

Every machine has various systems designed to per- form a specific function or type of work. As with all machines, when the machine works it creates numerous stresses on all the system within that particular machine. Feedback is required to monitor each system

to ensure the machine is functionally optimally. All the systems must work together to ensure the machine performs these functions as they were designed. The human body is a machine that provides us with the abil- ity to move efficiently and effectively. Just as machines are designed to perform a certain amount of work, every human body is designed to perform a certain amount

of work that needs to be performed. When we perform work it stress the body based on the amount of stress imposed upon it. Too much stress can cause a system or group of systems to under-perform or break down. This is especially true when we exercise. Exercise is considered a stress (anything beyond the body’s steady state of functioning). At this point it is important to note that the stress of exercise does not only affect the muscles of the body, but rather the body as a whole.

Just as most machines have various systems to make it work effectively, so does the human body. While science divides the body into eleven major “systems” (the circulatory can be divided into the cardiovascular and lymphatic systems as described in some textbooks described as twelve systems), one needs to remember that the body works as an integrated unit and that every system of the body is affected by exercise (albeit some more than others). So before detailing specifics on the primary effects of exercise on the various bodily systems, here is a brief review of the systems of the body that coincide with the systems of mechanical machines.




Skeletal Creates the basic structure of the body, giving framework to the muscular system to allow movement (levers, joints for pulley systems, axes of rotation). Also the site of blood cell formation.
Muscular Specialized cells of the body with contractile ability (create force) for causing/ creating movement/motion. Muscles are considered the body’s motors/engines for making motion as well as a fuel tank.
Nervous The body’s means of perceiving (sensors) and responding (actuators) to events in the internal and external environments. The CNS (Central Nervous System – the brain (body’s computer) and the spinal cord) and the PNS (Peripheral Nervous System). Both the CNS and PNS make up the body’s electrical and communication systems
Circulatory The “transportation” (plumbing) system of the body (O2, CO2, fuel, nutrients, waste, immune cells, hormones, etc.). Often divided into the cardiovascular system and the lymphatic (filtering) system
Respiratory Brings in O2 from the air and excretes CO2 and waste.
Gastrointestinal Use of ingestion, digestion, absorption, and metabolism to convert consumed fuel into smaller molecules for use in the body and excretes the unused remnants.
Integumentary The covering of the body (skin, hair, nails). Provides protection, structure, and serves as a sensory interface with the external environment
Urinary Creates, stores, and eliminates urine (which contains by-products [mainly nitrogen rich) of cellular metabolism). Kidneys considered a filtering organ
Reproductive Contains the gonads/sex organs for development of offspring
Immune Protects the body by distinguishing between the body’s cells/foreign substances and provides mechanisms to neutralize and/or destroy.
Endocrine Like the nervous system, serves as a communication system. Produces chemicals (hormones) which act as chemical messengers to signal changes for the body

Of particular interest here is the relationship of the term “engine” in mechanic machines verses the human machine. Muscles are the body’s engines since they are responsible for producing force to make motion pos- sible (more information will be discussed on this topic in Learning Module One). Note that each system has a primary function. Please also note that each system has numerous parts which make up that particular system without these parts the specific system being monitored will not function correctly unless each part is working properly. Whether in a normal functioning state or during a state stressed beyond normal, all the systems work together to optimize the specific performance desired.

Also notice the terms highlighted in the above chart for each bodily system. All these highlighted terms are specific to mechanics which all relate to machines and the various types of machines. This correlates back to our original supposition that the human body is likely the most advanced machine ever conceived. While most machines are limited to a specific type of work, the human body has the ability to perform numerous types of work not capable by many machines but has the capacity to adapt to numerous and ever-changing stresses imposed upon it for improving work capacity and efficiency of movement for doing work at various speeds (RATE of doing work i.e. various levels of power output). Let us ponder this scenario: An automobile mechanic, to maintain the working condition of an automobile, must know how all the systems of an automobile function properly. However, to maintain these systems the technician must also know every part/element within any system. Knowing every part (element) of a system facilitates one’s ability to correct any problem a system encounters (i.e. make the system function properly again). This analogy can be compared to a strength coach/personal trainer who designs a strength training program for any individual. One can “copy” a particular training program based on its theoretical basis (what the program is supposed to do) but is this selected program the best solution for the trainee to achieve said/specific goal(s)? The coach/trainer must first perform diagnostic tests (analysis, evaluation) to determine if any problems inhibit the trainee from training accordingly. Once all the diagnostic tests have been performed, the next step is to determine how to “fix”, “repair”, “augment” this machine for improved performance. To augment the human body, one must know the systems involved in physical training, the parts (elements) within the systems, and how applied stress (eustress versed distress) can alter the overall effectiveness of the human body.

Upon postulating the human body is indeed a machine, we must realize that mechanical principles do apply to human motion. These mechanical principles are utilized in the field of biomechanics. Numerous definitions from various sources attempt to explain what biomechanics is. Biomechanics is a complex field involving various branches of science; however, for simplicity, let us review what biomechanics is comprised of.

biomechanics hierarchy chart

Biomechanics is intimately related to kinesiology (the study of human movement). While biomechanics deals with the forces that cause movement, we must first observe how kinesiology examines the structure and function of the human body i.e. the kinetic chain, or the force-producing elements affecting the various types of motion performed by the human body. Reviewing the basics of Kinesiology is our starting point to determine all the aspects of force production which, in turn, affects power production (power is the RATE of work performed).

In conclusion, understanding the body as the ultimate machine gives one an interesting perspective for becoming a physical training professional. To optimize training for this amazing human machine one must know all the systems and their related elements (parts), how all the parts within a system function, then use this information efficiently and effectively to maximize human performance at any level as well as minimize the risk of injury.