The Anatomy and Physiology of Working Out
There are virtually hundreds of workout tutorials, guides, instructions, and shows on the Web and on Youtube – some of them really good, for the very fit and agile!
But, not much for the mere normal ones who have crossed the ‘midlife crisis’ bridge, on the wrong side of weighing scale, or with decades of sedentary lifestyle fueled by burgers, fries, and colas. For the normal souls, jumping into a workout regimen following those tutorials may well be the recipe for a disaster — I have come across quite a few horror stories within my own circle where people ended up inflicting upon themselves injuries – torn ligament, and worse.
The problem is that many younger trainers (and the youtube stars!) – lacking proper education and training themselves and bursting with the energy and vitality of youth, don’t understand the physiology and condition of people who have become vulnerable due to advanced age or a prolonged inactive lifestyle.
At this point, our intention here is to present a complete workout regimen for the average people – like you and me, as a guide to help them come on track to fitness — Fitness here is defined as a healthy physical and mental state; full of vibrance, flexibility, agility, vitality, and endurance.
But, before jumping into the workout binge, it will be a good idea to review and understand the physiology of exercise and anatomy of our body first — within the bounds of the scope of this article.
Understanding The Anatomy
The Heart
The heart can be considered the center of the body. It is located under the ribcage in the center of the chest between the right and left lungs. Its muscular walls beat, and contract, pumping blood to all parts of our body – including the brain. It is, without any doubt, the most efficient and hard working pump in the world.
It faithfully keeps on pumping the blood to every part of our body – without any complaints, providing us the life energy — as long as we take care of it and keep it in good shape. Life becomes really painful and comes to a painful end when this pump starts complaining – Taking the loving care of it is paramount.
The Heart is composed mostly of muscles – The Cardiac Muscles – cardiac muscles are responsible for pumping blood throughout the body. Regular cardio workouts are essential to keep these muscles get conditioned, healthy, and strong.
But, remember; it is the matter of heart – You have to take it easy and start working on it slow. It takes time to condition the heart and to make it adopt to heavy load of physical work.
Joints — The Tendons and Ligaments
When starting any workout regimen or activity, one has to be vey careful about not over stretching and injuring the fibers of the tendons and ligaments. If not well conditioned, they are quite prone to injuries.
The most common ligament injury is a condition that is referred to as sprain. Sprain results when a ligament or tendon is stretched too much and is unable to return to its resting form or when you move a joint rather harshly without warming up prior to exercise. The more sever form of injury is a tear or rupture in the fibre of the ligament or tendon – And, those injuries are difficult to heal.
Tendons and Ligaments connect all our joints in body. Wherever two bones or muscles meet, these fibre are there to connect them. Both the Tendons and Ligaments are made of fibrous connectivity tissues.
The differences in the Tendons and Ligaments are in the connections that they make: Tendons are the fibers that bind muscle to bones while Ligaments bind bone to bone. More precisely; a Tendon is a fibrous connective tissue which attaches muscle to bone. Tendons may also attach muscles to structures such as the eyeball. A tendon serves to move the bone or structure.
A ligament is a fibrous connective tissue which attaches bone to bone, and usually serves to hold structures together and keep them stable. The elasticity of the fibrous structure allows them to change shape and lengthen under stress and then return to their original shapes.
There are several distinct functions of Ligaments and Tendons in the human body.
1. Control & Define Range of Motion:
First, the ligaments/tendons – working in group, facilitate the movement of joints. They support the structures that keep a joint from becoming dislocated by limiting its range and direction of motion — This serves to stabilize the joints.
2. The Shock Absorber — Provide a Cushion:
Ligaments and Tendons act as shock absorbers protect the bones from scratching each other. For example, the ligaments in the spine protect the vertebrae from a sudden change of posture or when we lift a heavy object.
3. The Function of Proprioception:
Ligaments and Tendons in our body comprise of small receptors which are called Proprioceptors. These proprioceptors act as the informer – you may call them spies, albeit the good ones, of the brain. Whenever we perform an activity that involves stretching the joints and compressing or contracting the muscles, a message is sent to the brain by these receptors. It gives brain the perception and knowledge of the position of any joint in the body, thus maintaining the correct posture and movement of the body as a whole.
It is essential to treat these ligaments and tendons with loving care, and with all due respect!
The Muscles – The Musculoskeletal System
The primary purpose of the musculoskeletal system is to define and move the body. To provide efficient and effective force, muscle adapts to demands. In response to demand, it changes its ability to extract oxygen, choose energy sources, and rid itself of waste products.
Muscles are what give our body the defined structure and that posture and strength that we all yearn for. Beside those visible muscles, we have other groups of muscles that work from behind the scene — keeping our inner structure and internal organs securely hold in place.
Muscles can be divided into three distinct groups.
Visceral Muscles:
Visceral muscles are found inside of organs like the stomach, intestines, and blood vessels. These muscles provide motor power for regulating internal environment related to digestion, circulation, secretion and excretion etc.
They are controlled by autonomic nervous system; meaning: as for as our conscious brain is concerned, they are involuntary in their action – They cannot be moved at will – unless you are higher up in meditation.
Also, they respond slowly to stimuli but are capable of long time sustained contractions. They do not get fatigued easily.
Skeletal Muscles:
Skeletal muscles are the voluntary muscles — they are controlled consciously. These muscles attach to bones and their contraction facilitate the movement of our skeletons. That is why they are called skeletal muscles!
Every physical action that we consciously perform (e.g. speaking, walking, or writing) involves skeletal muscles. Most skeletal muscles are attached to two bones across a joint through tendons. Through their contraction, these muscles serves to move parts of those bones closer to each other.
Skeletal Muscles respond the quickest to workouts and provide the bulk to body.
Cardiac Muscle:
Cardiac Muscle is found solely in the walls of the heart. It contracts in response to signals from the Cardiac Conduction System. The heart wall itself is composed of three layers. The middle layer, the myocardium, is responsible for the heart’s pumping action.
Myocardium is the layer that is composed of Cardiac muscle. This muscles contracts in response to signals from the cardiac conduction system to make the heart beat.
Cardiac Muscle has similarities with skeletal muscles in that it is striated, and with smooth muscles in that its contractions are not under conscious control. However, this muscle is highly specialized. Though it is under the control of the autonomic nervous system, contractions can occur even without a nervous input due to cells called pacemaker cells. Cardiac muscle is virtually fatigue proof due to the presence of a large number of mitochondria, myoglobin and a good blood supply allowing continuous aerobic metabolism.
But, Cardiac Muscle need to be conditioned and workout most to keep them healthy, flexible, and strong — for a strong and reassuring ‘tick’.
The Connectivity Tissue:
Our abdominal cavity contains a plethora of organs – some of them quite large and bulky. Liver itself weighs around 3.5 lb (1.6 kg).
The ‘mesh’ of tissues that keeps everything in place is Peritoneum. The peritoneum is thin membrane that lines the abdominal and pelvic cavities, and covers most abdominal viscera. It is composed of layer of Mesothelium (Mesentery) supported by a thin layer of Connective Tissue.
The main function of mesentery is that it serves as a conduit for blood vessels, nerves and lymphatic vessels going to and from the organs.
Blood vessels, lymph vessels, and nerves are also embedded within the Mesentery structure. In addition to keeping all the organs in place, this connective tissue is also where the intestines get their blood supply. All the abdominal organs use this connective tissue for their nutrition supply as well.
Body’s Physiologic Adaption to Workout
Our bodies are naturally tuned to adapt to the demands of the workload that we impose upon it. Heart muscles – entire cardiovascular system, musculoskeletal system, internal organs and connectivity tissue, and the ligaments & tendons all grow stronger to meet the increased demand that is placed on the body — It is amazing to observe the evolutionary responses of the nature!
It is very interesting to read through the information to understand the Physiologic Responses and Long-Term Adaptions to Exercise by our body. It gives us a perspective of the mechanism involved in the recovery and growth of our physical and neurological form.
When challenged with a physical task, the human body responds through a series of integrated changes in function that involve most of its physiologic systems. Movement requires activation and control of the musculoskeletal system; the cardiovascular and respiratory systems provide the ability to sustain this movement over extended periods. In response to regular exercise, each of these physiologic systems undergoes specific adaptations that increase the body’s efficiency and capacity.
The body’s physiologic responses to episodes of aerobic and resistance exercise occur all across the body — in the musculoskeletal, cardiovascular, respiratory, endocrine, and immune systems.
The Cardiovascular System, composed of the heart, blood vessels, and blood, responds to the increased demands of exercise. The cardiovascular response to exercise is directly proportional to the skeletal muscle oxygen demands for any given rate of work. This demand, when sustained over a time, forces the entire cardiovascular system to grow in strength and efficiency.
The Muscles – The Musculoskeletal System responds by adding mass and fiber strength to its structure. Skeletal muscle is the most adaptable tissue in the human body and muscle hypertrophy (increase in size) is most noticeable in response to stress put upon it. Len Kravitz, Ph.D. University of New Mexico, Department of Exercise Science, explains the physiology of human muscles growth in his essay How do muscles grow? quite well:
Trauma to the Muscle: Activating The Satellite Cells:
Resistance training leads to trauma or injury of the cellular proteins in muscle. This prompts cell-signaling messages to activate satellite cells to begin a cascade of events leading to muscle repair and growth. Several growth factors are involved that regulate the mechanisms of change in protein number and size within the muscle. The adaptation of muscle to the overload stress of resistance exercise begins immediately after each exercise bout, but often takes weeks or months for it to physically manifest itself. The most adaptable tissue in the human body is skeletal muscle, and it is remarkably remodeled after continuous, and carefully designed, resistance exercise training programs.
The disruption to muscle cell organelles activates satellite cells, which are located on the outside of the muscle fibers between the basal lamina (basement membrane) and the plasma membrane (sarcolemma) of muscles fibers to proliferate to the injury site (Charge and Rudnicki 2004). In essence, a biological effort to repair or replace damaged muscle fibers begins with the satellite cells fusing together and to the muscles fibers, often leading to increases in muscle fiber cross-sectional area or hypertrophy. The satellite cells have only one nucleus and can replicate by dividing.
As the satellite cells multiply, some remain as organelles on the muscle fiber where as the majority differentiate (the process cells undergo as they mature into normal cells) and fuse to muscle fibers to form new muscle protein stands (or myofibrils) and/or repair damaged fibers. Thus, the muscle cells’ myofibrils will increase in thickness and number. After fusion with the muscle fiber, some satellite cells serve as a source of new nuclei to supplement the growing muscle fiber.
With these additional nuclei, the muscle fiber can synthesize more proteins and create more contractile myofilaments, known as actin and myosin, in skeletal muscle cells. It is interesting to note that high numbers of satellite cells are found associated within slow-twitch muscle fibers as compared to fast-twitch muscle fibers within the same muscle, as they are regularly going through cell maintenance repair from daily activities.”
Exercise also has been shown to bolster the function of certain components of the human Immune System—such as natural killer cells, circulating T- and B-lymphocytes, and cells of the monocyte-macroph- age system—thereby possibly decreasing the incidence of some infections (Keast, Cameron, Morton 1988; Pedersen and Ullum 1994; Woods and Davis 1994) and perhaps of certain types of cancer (Shephard and Shek 1995).
And, Into The Joys of Workout
Proper exercises and workouts keep the these Connectivity Tissues strong and healthy – we wouldn’t like any of our organs protruding and dangling around in our abdomen — or just stop functioning due to lack of nutrition.
Physical activity has numerous beneficial physiologic effects. Most widely appreciated are its effects on the cardiovascular and musculoskeletal systems, but benefits on the functioning of metabolic, endocrine, and immune systems are also considerable.
A thoughtfully planned regular workout regimen is immensely beneficial to our wellbeing. It promotes health, vitality and vigor, and, trust me on this one – it brings ‘joys’ to life that will also make your spouse / partner very happy!
— Have Fun — Enjoy a Vibrant Life —
☘ ☘ ☘ ☘ ☘
References Include:
- McArdle WD, Katch FI, Katch VL. Essentials of exercise physiology. Philadelphia, PA: Lea and Febiger, 1994.
- Chen W, Zhang Y, Liu JP. Physiologic Responses and Long-Term Adaptions to Exercise.
- American College of Sports Medicine. Position stand: physical activity, physical fitness, and hypertension. Medicine and Science in Sports and Exercise1993;25:i–x.
- National Institute on AgingYour Heart
- Rowell LB. Human cardiovascular control. New York: Oxford University Press, 1993.
- Thompson PD, Dorsey DL. The heart of the masters athlete. In: Sutton JR, Brock RM, editors. Sports medi- cine for the mature athlete. Indianapolis: Benchmark Press, 1986:309–318.
- Len Kravitz, Ph.D, Albuquerque: University of New Mexico, Department of Exercise Science. How do muscles grow?
- Intro to Human Body – Structure of Skeletal Muscle
- National Institutes of Health Sprains and Strains of Ligaments, Muscle, or Tendons
- Washington State Univarsity – BIOLOGICAL SYSTEMS ENGINEERING Structure and Function of Ligaments and Tendons
- National Heart, Lung, and Blood Institute Integrated Guidelines for Cardiovascular Health and Risk Reduction
