PE Part 1
PE Part 1
PE Part 1
1
Musculoskeletal System
In this module, you will be able to learn about the Musculoskeletal System, its
functions, and importance to your body. The topics will cover how you can
specifically improve this organ system to make you more efficient and
effective in your different activities.
At the end of this module, you will be able to:
1. learn about the basic Human Anatomy and Physiology of the
Musculoskeletal System.
2. know the benefits of regular physical activity and exercise to the
Musculoskeletal System.
3. identify the different factors that contribute to the development of
cardiovascular endurance, muscular strength and endurance.
4. gain knowledge on different health-related diseases and risk factors that
can be acquired from failure of developing this organ system and how
physical fitness can lessen these specific health risks.
5. gain knowledge on the proper exercise prescription and other factors
that can develop the improvement and health of the Musculoskeletal
System.
6. learn basic exercise activities and the muscle groups that are involved for
each type of movement.
7. perform basic exercises that would develop muscular strength and
endurance.
8. critically evaluate the physiological effects of exercise to the different
organ systems of the body;
Within the module, you will be able to learn about the different topics:
Basic Human Anatomy and Physiology of the Musculoskeletal System
Function & Importance of Musculoskeletal System
Absolute Strength vs. Relative Strength
Muscular-related conditions and diseases - different factors that affect
its growth and development
Benefits of Exercise to the Musculoskeletal System
Common myths and superstitions about resistance training
Tail Bone
Humans have a very small tail-looking bone attached at the base of the spine. This
bone is known as the coccyx. It is composed of 3-4 very small bones that are fused
together. This is the bone that you feel at the lower base of your spine when you are
seated for a prolonged period.
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Musculoskeletal System
Can you imagine your body without bones? What would you look like? How do you think it
would feel like? What do you think are your bones made of?
Without these chief organs, your body will have no concrete form, you would have poor
ability in keeping your posture intact, and movement will be very impossible.
The most important structure that keeps your body in solid form are your bones. Bones
are a big part of your body that are structurally made up of clusters of proteins called,
collagen and minerals (e.g. calcium and calcium phosphate).
These materials then join and work together to give your bone its compact and sturdy
characteristics.
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Musculoskeletal System
Appendicular Skeleton
The Appendicular skeleton is the part of your body composed of the upper and lower
limbs. In total, this region of the body is composed of 126 bones that help and allow
you to move and manipulate your body in different directions.
Though they possess these qualities, bones remain hollow within its structure. This is
because bones are also important sites on your body that produce blood, contain
numerous blood vessels, and bone marrows that all help aid in several functions within
your system.
There are a total of 206 bones within your body, each of them consisting unique
characteristics and functions. But, despite its number, bones are lightweight in nature,
giving you the ability to easily carry them around.
Since there are several kinds of bones found within your body, its structures also come
in several variations. But generally, bones that are found within your limbs (Axial
Skeleton) are made up of two main parts and these are:
a. Shaft/Diaphysis – the part of the bone that is long and straight holding all its
other parts together.
b. Growth Plate/Spongy bone – this is seen on top of the shaft that start off as
soft/spongy bone and grows off as maturity begins and are transformed into
mature bone structures that are more compact and hard.
Other parts of the bone that are found within its hollow structure are:
c. Bone marrow
d. Blood Vessels
These specific bone structures conjoin together within your body making you a
skeletal framework.
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Musculoskeletal System
Bones, like other organ systems in the body provide several important functions like:
1. Protection
Bones have the capacity to contain several internal organs and blood vessels within the
body. They serve as the structure that holds these vital organs in placed.
Without bones for protection your insides will be exposed to danger and deformation,
making you prone to a long list of bodily complications.
These are the main bones that protect your critical organs: the rib
cage (which mainly protects the heart, lungs and other vital organs),
the skull (which protects the brain), the spinal column (which
protects the spinal cord), and the pelvic bones (which protect the
reproductive organs).
Image Source:
Rib Cage - https://github.com/leshy/ribcage
Skull - http://spina.pro/anatomy/kosti/kosti-golovy/klinovidnaja-kost.php
Pelvic bone - http://humananatomybody.info/anatomy-of-respiratory-system/
Spinal Column - http://www.spinalinjury101.org/details/anatomy
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2. Body Shape
They serve as the support and frame of your body. Without bones you would be
gelatinous in nature, crawling around without form just like amoebas.
Since it has the ability to give your distinct shape and form, body shape therefore
becomes unique for every individual. Did you notice that there are people who are lean
and tall, while there are those who are broad and bulky?
Your shape is different from other people because of factors like: hereditary traits,
ethnicity, and gender. In fitness, these shapes and physically visible characteristics that
people have are known as body types.
The structure of your bones and body tissues are a big factor in determining your body
type. There are three (3) different classifications of body types, and these are:
a. Ectomorph –a body type described to have a thin and long bone structure.
b. Endomorph –a body type which has a bulkier and bigger bone structure
c. Mesomorph – a body type that’s leaning on the muscular side/physique.
Image Source:
Body Types (male) - http://www.muscleyourway.com/fitness/body-types-ectomorph-mesomorph-
endomorph/
Body Types (female) - https://fitterfaster.wordpress.com/2013/01/
Which among these body types does your body fall in to? I hope you now understand
that each shape is unique and it varies from person to person.
This is the reason why no matter how some people try their hardest to get lean and be
in shape the same way as magazine models do, this is very impossible. Your bones have
something do with the uniqueness that you possess.
The Skull
Your skull is actually composed of 28 different kinds of bones that are perfectly
fused together to serve as the compartment of your brain.
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Musculoskeletal System
3. Movement
Bones are able to generate and transfer forces to
individual parts of your muscles, tendons,
ligaments, and joints. With this function, they
also serve as places for attachments for several
muscles found within your body.
4. Blood Production
Another function of the bones include, production of blood cells within your body.
Remember that bones are structured sturdy and hollow? Aside from containing many
blood vessels, these hollow walls of bones are the actual sites where blood is produced.
Ever heard of bone marrow? This is the material found within the hollow walls of your
bones which are responsible for producing different kinds of blood cells. These blood
cells specifically help in protecting your body from foreign bodies (white blood cells),
in distributing oxygen and nutrient-rich blood throughout your entire system (red
blood cells), as well as, aid in the blood-clotting ability of your tissues (platelets).
These marrows can come in different colors (e.g. yellow, red, pink) depending on their
location in the bones of the body. All of these forms of marrow are responsible for
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Musculoskeletal System
providing the body with new blood cells that are responsible for tissue healing, oxygen,
and nutrient supply.
This ability of bones to produce these blood cells could also come handy especially
when, the healing process of a wound begins; the bones always provide your body with
new blood cells to replace what was lost, aiding in your quick recovery time.
All these four (4) functions (i.e. protection, body shape, movement, & blood production)
make bones such an integral part of the human body. Without it, your body will not be in a
state of equilibrium or balance.
The Vertebra
Your spine is known in medical terms as the vertebra. It is composed of 33 bones that
are composed of the cervical, thoracic, lumbar, sacrum, and coccyx. These vertebra
houses and protects your spinal cord from compression and stress.
What do you think are factors that can contribute to your body’s bone degeneration?
1. Age
First factor that can affect the rate at which your
bone degenerates is age.
As you slowly lose the density of your bones, it also becomes less compact and sturdy
making you more prone to bone breakage.
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Musculoskeletal System
Together with your bone density loss, as you age, motor nerves within your body lose
their connections to the nervous system. When this happens, you begin to move slower
and you become less coordinated with your movements.
2. Injuries
Injuries can be caused by many factors (e.g. accidents, weak bones). They can come in
different forms like the ones in this example:
Image Source:
Bone Injuries - https://www.pinterest.com/pin/356769601701694244/
If left untreated, these bone injuries may cause Calcium deposits (found within your
bones) to leak into other parts of your body. Calcium is a mineral found in bone that
gives bones its hard and sturdy characteristics.
Continuous leakage of these calcium deposits within other parts of your body may
further break or destroy other bones, muscles, tendons, and ligaments that may cause
you more problems. That’s why, it is advisable that if such incidents occur, you
immediately need to seek medical attention.
Short Bones
Your hands and feet are parts of your body that contain different small bones that
allow you to do motor skills with ease. These bones are sites of attachments for many
muscles, tendons, and ligaments that help you execute several kinds of movements
that are static or dynamic in nature.
Your hormones also play a huge part in regulating these chemical processes. If they are
not well-produced by your body, bones lose their structure and they become weak and
brittle.
This condition is known as Osteoporosis and, it is more common for females than
males. When women have a deficiency of calcium and Vitamin D, bones lose their
structure and slowly deteriorate in the process, making it brittle and prone to
breakage.
Image Source:
Bone Density Loss -
http://www.scottsdalesportsmedicine.com/content/dexa-
bone-density-scan
The lack of hormonal production in women once their menopausal stage takes place,
causes the bones to lose the necessary nutrients it needs to maintain its integrity. As
this starts and progressively happens, bones become extra light and become more
prone to breaking because they are have become soft and brittle.
4. Nutrition
The types of food you eat can directly affect the compounds that make up your bones.
Do you like to eat broccoli? Do you consume dairy products? How about fish? Are you a
fan of eating seafood?
These food in the picture are just examples of food that are rich in calcium and Vitamin
D. These are some of the nutrients that your bones may utilize to maintain its health.
Drink up!
One of the major sources of calcium in food sources comes from animal milk.
Drinking milk provides the body with the enough calcium and proteins it needs to
effectively calcify and harden the bones of your body. Including this in your diet
would help prevent bone density loss and injuries from occurring.
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Musculoskeletal System
Image Source:
Nutrition - http://www.precisionnutrition.com/all-about-
bone-health
Dairy products like cheese, bread, and milk are good sources of calcium while broccoli
and sardines are food sources that contain high doses of vitamin D.
Image Source:
Ligament & Tendon -
Image Source:
http://solidlifefitness.com/2014/03/16/muscles-
Joints of the body -
tendons-ligaments/
http://www.med-
health.net/Sudden-Joint-Pain.html
Unlike bones that are hard and sturdy, connective tissues are structures of the
musculoskeletal system that are made up of fibrous and elastic materials. These connective
tissues are ligaments, tendons, and joints.
a. Ligaments
These connective tissues are a part of the musculoskeletal system which attaches
bone to another bone.
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Musculoskeletal System
b. Tendons
These are connective tissue structures that attach bone to muscles.
c. Joints
These are connective tissue structures in which bones meet and are surrounded by
pockets of synovial fluid that provide several range of motions possible.
Some of the joints of the body are found at the shoulders, elbows, wrists, hips, knees,
and feet. Without these joints, daily movements like pushing, pulling, lifting, or
dropping objects are not going to be possible.
These connective tissues specifically cushion bones, allow bones to freely move without
friction, and connect important parts of the body together.
Joint Injuries
Joints are also parts of the body that can be prone to injuries. A condition known as
bursitis, is acquired by a person through repetitive movements done for a long
period. In this condition, the joints become inflamed and painful due to the
accumulation of fluid substance within its sacs. This hampers a person from moving
because of the decrease in the Range of Motion of the body part.
You will notice how important strength is in terms of training for a sport or simply
performing daily activities. You will also discover that height and built doesn’t necessarily
have anything to do with strength. Prepare to debunk notions in your head that if you are
bigger you are stronger through learning about the differences of absolute and relative
strength.
Before learning about absolute and relative strength, can you still remember the two
health-related fitness components related to the functions of your bones and muscles?
Muscular Strength and Muscular Endurance are the two health-related fitness
components related to the musculoskeletal organ system.
Can you still recall their difference? From the previous lessons, muscular endurance refers
to your ability to resist fatigue. This refers to how long you can withstand muscular
contractions like in running marathons, swimming, or activities that go for hours.
While muscular strength has something do with your ability to generate force during a
maximum effort. Recall that, this component of fitness also has something to do with
explosive movements and how you generate your muscles to produce effort with such
great force.
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Musculoskeletal System
Knowing these two again, it will be easier for you to understand and differentiate between
absolute and relative strength.
The easiest way for you to understand this is through this example:
When you are able to lift a maximum number of weight (kilograms or pounds) only in
one attempt, you have absolute strength.
Usually absolute strength is associated with highly trained individuals who have been
engaging in a specific sport of their liking for some time.
The best sport example for absolute strength is the sport of Power lifting and Olympic
Weight Lifting. This is a sport in which a person attempts and successfully performs lifting
a weight at its maximum with all his/her efforts.
Simply put, relative strength has something to do with your built (e.g. weight, height, body
composition). It focuses more on the ability of your muscles to contract and exert force
through the current structure you have available.
To better understand the concepts that go with absolute strength and relative strength,
take a look at this example:
Knowing about absolute strength could help you determine your relative strength. This
way, you will be able to gauge how much weight you can tolerate lifting in exercise,
Analyzing the data in these two examples, Person A has more relative strength than
Person B.
Even if Person A is smaller, his body weight is still more able to lift a heavier load of 2.5
lbs. compared to person B who was only able to lift 2 lbs of weight.
vs.
III. Muscles
Knowing all the details about the bones and the
relationship of its structures to strength and
endurance, this part of the lesson will focus on
the muscle tissues of the musculoskeletal system.
Since bones are sites of attachments of connective tissues, muscles on other hand are
responsible for exerting force towards the bones. They are directly aligned to bones to
enable the push and pull motions it does during each movement you do.
Aside from all these things, muscles are also responsible for keeping the shape of your
body and in holding your bones altogether.
Can you just imagine your body without muscles? What would you look like? Do you think
movement will be possible?
1. Skeletal muscles
2. Smooth muscles
3. Cardiac Muscles
In this part of the lesson, you will be able to know a great deal about the skeletal muscles
and how they function to help you in your movements.
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Musculoskeletal System
1. Skeletal Muscles
Your Skeletal Muscles are the muscles that you use for movements. Skeletal muscles
are distinct in their shape because they are long and cylindrical allowing your body to
move and perform work.
These muscles are also voluntary in nature, meaning you can control when they will
move and how fast they will move. They are controlled by the brain and the nervous
system and they help you in generating actions and movements in your everyday life.
Examples of activities that involve your skeletal muscles are: bending your elbow,
performing an exercise routine, and flexing your trunk. Several muscles that are found
attached to your bones, ligaments, tendons, and other muscles, all work together to help
support you in your movements.
All skeletal muscles have a general basic structure that enables it to respond to stimulus
and perform its different actions.
These structures are pact together to form muscle groups that make-up the totality of
your skeletal muscles.
The Connective Tissue or Epimysium, on the other hand, are structures responsible
for covering these bundles of myofibrils. Without the Epimysium, muscles will spread
apart and will not be pulled together efficiently.
Other important structures of the skeletal muscles are the motor units and muscle
fibers.
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Musculoskeletal System
The muscle fibers are groups of myofibrils that contract and relax through
movements. Just like your myofibrils there are also millions of these muscle fibers
located in different parts of your body.
The motor units are nerves connected to these muscle fibers. These are parts of your
skeletal muscles that are responsible for transmitting chemical energies to your spine
and brain, which are the control centers of your body. When these motor units send
signals to these channels, movements and reactions become possible.
Muscle Fiber
Image Source:
Motor Unit - https://www.t-nation.com/training/secret-to-motor-unit-
recruitment
The bigger your muscle fibers are, the more motor units it contains. This is for actions
that require heavy movements like the muscles located in your legs. They carry your
weight all the days of your life and that alone requires a lot of effort. Compared to the
muscles of your arms your legs have a greater number of motor units to support this
type of activity and other activities.
In the same way that, the smaller your muscle fibers are, the less motor units are
attached to it. Like the muscles of your arms in comparison to the muscles of your
abdominals.
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Musculoskeletal System
Without motor units sending several impulses to your brain and to your spine, you
won’t be able to perform simple movement patterns that you do on a daily basis. These
motor units serve as the control center of your muscles and their functions can best be
improved through exercise and practice.
Why do you need to learn this? For you to be aware that everything happening inside
your body is a result of several chemical reactions that take place within the
connections of your musculoskeletal system, your spine, and your brain (collectively
known as Central and Peripheral Nervous System).
2. Cardiac Muscles
From the previous lesson you already know that the heart is a specialized type of
muscle in the body.
These muscles are controlled by the functions of the brain and they work non-stop, even
while you are asleep.
Your cardiac muscles have a unique thick and sturdy muscle cell to support its pumping
action.
3. Smooth Muscles
The Smooth Muscles are known as involuntary muscles.
What do involuntary muscles mean? These muscles work day-in and day-out without
your effort. They perform their work at a regulated pace even while you are asleep.
Your smooth muscles have thin and smooth muscle cells that contract and relax to move
food and waste products out from your body when you’ve consumed food or liquid
products.
The smooth muscles can be found within and covering the internal organs of the body
like the stomach, intestines, and liver. What do these muscles do?
Image Source:
Types of Muscles -
http://pennstatehershey.adam.com/content.
aspx?productId=117&pid=2&gid=19841
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Musculoskeletal System
Each muscle type is unique, and each perform different functions within your body. They all
work hand-in-hand with your brain and spinal cord, to allow you to become efficient and
healthy.
Without these muscles, your body will have a hard time maintaining its chemical processes,
ultimately leading you to experience disease and other health complications.
Does it seem like you are failing because you cannot endure the stress you’re putting your
body in to? Or did your feel the exact opposite?
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Musculoskeletal System
If you felt the exact opposite, your slow-twitch muscle fibers are more at work within
your skeletal muscles. This classification of muscle fiber refers to relatively fatigue
resistant muscles that don’t contract as rapidly and strongly.
When this happens, you are able to withstand longer bouts of activities easily. You might
not have discovered it yet because you may be starting from physical activity but slow-
twitch muscle fibers are an advantage in performing aerobic activities.
You might want to try swimming, joining a marathon or even try the sport of triathlon.
These are activities that can range for hours on end. If your body can resist these types of
activities and are resistant to fatigue, then your slow twitch muscle fibers are more
dominant within your body.
What other activities can you suggest that require your slow-twitch muscle fibers?
The second classification of skeletal muscle fibers are called, fast-twitch muscle fibers.
Unlike the slow-twitch fibers that can endure fatigue, the fast-twitch muscle fibers fatigue
rapidly. This is because these muscles tend to contract forcefully and
rapidly/quickly.
For this reason, fast-twitch fibers are used for anaerobic activities. Can you still
remember what anaerobic activities are?
During the previous discussions, it was mentioned that, anaerobic activities are activities
that require quick and explosive movements.
Remember the Vertical Jump Test you’ve performed for lesson 4? What skill related
component was it testing?
Recall that the activity tested your leg muscle power. In relation to the fast twitch muscle
fibers, all power activities are considered as anaerobic exercises because of their quick and
forceful nature.
If these fast-twitch muscle fibers are more dominant within your skeletal muscles, you are
able to perform activities like:
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Musculoskeletal System
Sprinting, Olympic Weight Lifting, and Plyometrics --- also known as jump training where
muscles are exercised for a short and effortful motion. These activities all require your
muscles to be well-conditioned and in sync in performing explosive activities.
Image Source:
Plyometrics – http://teamdoctorsblog.com/2012/05/16/video-tutorial-137-why-plyometric-jumping-or-
impact-exercises-increase-the-level-of-human-performance-in-athletes-and-you-too/
Sprinting – http://www.stack.com/a/sprinting-form
Snatch series – http://www.theboxmag.com/article/why-snatch-9780
Image Source:
Fast twitch muscle fiber- http://helpingthebesttogetbetter.com/?p=81
Slow-twitch muscle fiber - http://frontalcortex.com/?page=oll&topic=24&qid=1911
If you answered A is slow-twitch and B is fast-twitch, then you are correct. Under a
microscope fast-twitch muscle fibers have a darker color/shade compared to the
slow twitch fiber muscles.
Here’s another one, which is the fast and slow-twitch fiber among the two?
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Musculoskeletal System
If you answered A is fast-twitch and B is slow-twitch, then you are correct. You have
already understood the striations of the muscles and how they function within the
body.
Which muscle fiber do you think is dominant in your system? Are you a fast-twitch or slow-
twitch fiber-dominant? You can learn about this if you try to engage yourself in regular
physical activities.
Do you still remember your Ratings of Perceived Exertion or RPE? This scale can be a good
measure for you to determine which fiber is dominant within your body.
Remember that your body is composed of both fast and slow-twitch fibers, the amount at
which they are concentrated within your system varies. The most distinct feature about
these muscle fiber types is that its number is fixed at birth. Whatever you have inherited
from your parents, will also be carried on to your genes.
The importance of knowing this is for you to try exploring and learning about your muscle
fiber type, this way you will be able to determine for yourself which activities you can
surely see yourself improve on.
Here are two basic conditions that may take effect when you are engaged in an activity, you
are sedentary, or you have injuries:
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Musculoskeletal System
1. Muscle Hypertrophy
Generally, when you are engaged in regular physical
activity your body adapts to the load or stress you are
putting it into. As a result, you develop large muscle
fibers.
Hypertrophy is at work during this phenomenon. Due to regular physical activity your
muscles will grow larger in size making your muscles more defined, giving you a
relatively fit physique.
2. Muscle Atrophy
The exact opposite of muscle hypertrophy is
called, Atrophy. This is a condition in which
your muscles decrease in size.
If muscles are progressively left in small size, weakness will further continue and
cause further injuries to your body. What you simply need to do to prevent this from
happening is to actively move and engage in regular exercise.
Here are some factors that may affect your muscles’ growth:
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Musculoskeletal System
1. Genes
From the previous lessons it was mentioned how
your genes play a very large role in
distinguishing your physical characteristics.
Does your father have a good physique? How about your mother? Are one or both of
your parents leaning on the heavy side? This may probably explain your muscles
growth rate and size.
2. Gender
Second factor that can affect the rate at which your
muscle grows is, your gender.
3. Age
Third factor is, your age. The older you are, the
harder it is for your muscles to endure the load
and stress you are putting it into.
But, once you go beyond the age of 30, your strength starts to decrease and you can
no longer perform the same way you did when you were younger.
Your age also contributes largely at the rate at which your muscles are deteriorating.
Motor units within your muscle fibers slowly decrease its number making you less
coordinated, which can be further exaggerated especially when you are living a
sedentary lifestyle.
Image Source:
Running - https://www.washingtonpost.com/national/health-
science/high-tech-workout-gear-can-improve-your-performance-along-
with-your-appearance/2011/08/23/gIQAaFpfnJ_story.html
Yoga - http://www.posture-alignment.com/sports.html
Aside from this, you will have enough energy for recreational activities and it will be
possible for you to achieve higher levels of performance because your muscles and
bones are active and strong.
A fit and strong set of muscles and bones can prevent this
from happening. Your posture and your good body
mechanics are the direct manifestation of a strong and fit
musculoskeletal system.
Does your back hurt all the time? If you want to decrease
this, you must develop your abdominals and lower leg
muscles to make your muscles push and pull strongly in
their respective directions.
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Can you still remember what fat-free mass is? These are tissues within your body that
are found in your muscles and organs.
Image Source:
Improved body composition -
http://realhealthnutrition.com/what-fish-oil-can-
do-for-your-body/
When you look good, you feel good! Remember this? When you feel good, everything
else around you follows. You are more able to deal with things with a positive heart and
your self-esteem will definitely soar high.
Image Source:
Man flexing - http://menofvalue.com/2015/04/14/bodybuilding-for-beginners-tips-for-
training-lagging-muscles/
Woman measuring waist - http://www.mirror.co.uk/news/uk-news/health-seven-
simple-tests-that-can-874006
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Musculoskeletal System
Always remember that men will always have larger and stronger sets of muscles due to
hormones called, testosterone. While women on the other hand, will tend to lose
inches, increase their strength, and have toned muscles when developing the
musculoskeletal system.
You are preventing your nerves and muscles from degenerating fast and you are
securing a better quality of life for yourself in the long run.
Image Source:
Muscle degeneration - http://www.hughston.com/hha/a_14_2_3.htm
Nerve Degeneration - https://ghr.nlm.nih.gov/condition/spinal-muscular-atrophy-with-progressive-
myoclonic-
Potentially life threatening injuries like osteoporosis and bone density loss will be of
little concern for you because this organ system is strong.
Image Source:
Joints – http://pharmaworld.pk.cws3.my-hosting-
panel.com/ThermapeuticAreaDetail.asp?tId=16
Injuries –
http://www.medicinenet.com/rheumatoid_arthritis_pictures_slideshow/article.htm
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When your muscles and bones are strong, your LDL or Low-density Lipoprotein levels
changes as well decreasing your risk for fat-related diseases.
And lastly, as your bone mineral density increases it reduces your risks for
osteoporosis and other bone fractures.
Those are some of the many benefits of exercise to the musculoskeletal system.
Generally, as you age, the density of your bones and muscles decrease. But, the speeding
up of this process occurs when you are inactive, thus exposing you to many health-related
diseases.
The goal is for you to always aim at increasing or maintaining your muscle size and bone
density. What do you think is the best way to do this?
Regularly engaging in strength training is the best way of developing this organ system.
Image Source:
Exercise human anatomy - http://breakingmuscle.com/functional-fitness/why-crossfit-coaches-
need-anatomy-bones-muscles-and-lifting
Allotting at least three (3) times a week of body weight or weight lifting activities in your
life can be beneficial to your musculoskeletal system.
Along with this, if you progressively know how to alternate cardio training with your
strength training, the three different kinds of muscles (i.e. cardiac, smooth, & skeletal) in
your body will function more efficiently. Making sure that you are active and you are using
your body well can help you achieve a lifetime of health and fitness.
Most times, men are willing to engage and experiment with weight lifting or weight
training more than women. This is because a lot of myths, superstitions, and fallacies
about strength training have been circulating throughout the fitness industry.
Above are the list of fallacies, myths, & superstitions on strength training.
1. One loses flexibility
Engaging in resistance training would make you lose your flexibility. This is totally a
myth because, when your muscles and bones are healthy and fit, your joints,
tendons, and ligaments also become strong.
This way, you gain better range of motions for your joints preventing you from
injuries.
This is because the hormones that women produce, called estrogen, are the
hormones opposite from males. Testosterone hormones found in males are the
cause why they grow in sizes bigger than females, while estrogen does not have this
ability.
Women, may have a decrease in fat percentage making their bodies leaner but it
takes a lot of hard training, years of dedication, and strict diet to gain muscle mass.
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Your coordination is also greatly improved when you are performing strength
training because you are training your mind to get used to the stress you are putting
it into, eventually the movements become automatic.
This is because it is already becoming harmful to the body. The best thing to do is to
listen to your body, know when it is enough and know when to push through.
Conclusion
The factors that may contribute to the rate at which the musculoskeletal system improves
or deteriorates is inevitable. Moving and constantly choosing to do so will always be a wise
decision for you to make in able for you to improve this organ system’s functionality.
Developing your body through specific exercise training programs can help you in
achieving a lifetime of health and wellness.
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Glossary
Absolute Strength – the maximum amount of force a person can exert with his/her
maximum effort
Aerobic Training – “aero” which means, with the presence of air; a type of endurance
training which refers to long-lasting work-outs that have low to high-intensities.
Anaerobic Training – “anaero,” which means with the absence of air; a type of endurance
training which refers to short-lasting and high-intensity activities.
Axial Skeleton – classification of bones in the body that is composed of the upper and lower
limbs.
Blood Vessels – tissues that make-up the vascular system; responsible for transporting
blood and nutrients throughout the whole body.
Body Type – unique shape and physically visible characteristics based on a person’s bones
and body tissues; classifications include, ectomorph, endomorph, & mesomorph.
Bone Density – a measurement of the amount of calcium and other minerals found within
bones.
Bone Density Loss – a condition in which bones lose their calcium and other mineral
contents.
Bone Marrow – spongy tissue material found in the hollow walls of bones responsible for
producing blood cells (i.e. WBCs, RBCs, & Platelets).
Bone Stress – amount of force applied to the bone through physical exertion/effort.
Bones – structure of the body made-up of clusters of proteins called collagen and minerals
(e.g. calcium and calcium phosphate) that are joined together giving its sturdy
characteristics.
Calcium – a mineral found in bone that gives bones its hard and sturdy characteristics.
Cardiac Muscles – muscles that make-up the heart to help it perform its complex pumping
actions to supply the body with oxygen and nutrients.
Coccyx – 3-4 bones fused together, located at the base of the spine; also known as “tail bone,”
because of its resemblance to animal tail bones.
Collagen – type of organic material within the body that mixes with minerals to form bones.
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Connective Tissues – tissue structures in the body composed of ligaments, tendons, and
joints.
Diaphysis – the part of the bone that is long and straight holding all its other parts together.
Ectomorph – a body type described to have a thin and long bone structure.
Endomorph – a body type which has a bulkier and bigger bone structure
Epimysium – structures that are responsible for covering bundles of myofibrils into their
compact state.
Fast-twitch Muscle Fibers – skeletal muscle fiber type that easily fatigues because these
muscles tend to contract forcefully and rapidly/quickly; used for anaerobic trainings.
Growth Plate – end part of the bone that starts off as soft and spongy in nature, that hardens
as a person ages.
Minerals – type of organic material within the body that mixes with collagen to form bones
(e.g. calcium & calcium phosphate)
Motor Units – part of the skeletal muscles that transmit and send chemical impulses to the
brain and spinal cord to help the muscles contract and perform their actions appropriately.
Muscle Atrophy – condition in which muscles degenerate and decrease in size because of
injuries, age, & inactivity.
Muscle Fibers – groups of myofibrils that make-up bigger muscle groups in the body;
contracts and relaxes through movements.
Muscle Hypertrophy – condition in which muscle fibers develop and become enlarged
through exercise and regular physical activity.
Muscular Strength – the amount of force a muscle can produce with a single maximum
effort.
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tendons, & ligament work together; responsible for allowing the body perform different
movements.
Myofibrils –are the smallest structure of the muscles; millions of myofibrils pact together to
form muscle groups all over the body.
Osteoporosis – a medical condition in which bones become brittle due to hormonal changes
and deficiency in calcium or Vitamin D.
Pelvic bones – set of bones that house and protect reproductive organ systems and internal
organs located at the lower regions of the body.
Platelets – blood cell that aids in the blood-clotting mechanism of the body’s tissues.
Plyometrics – also known as jump training; muscles are contracted for short bouts with
high effort.
Red Blood Cells (RBCs) – blood cells responsible for providing the body with oxygen-rich
and nutrient-rich blood.
Relative Strength – the amount of force that can be exerted in relation to one’s body weight
or unit of muscle cross section.
Rib Cage – set of bones that house and protect the heart and lungs.
Skeletal Muscles – muscles that are used for movement and are voluntary done and
controlled by the brain and nervous system. (ex. bending your elbow)
Skull – set of fused bones that house and protect the brain.
Slow-twitch Muscle Fibers – skeletal muscle fiber type that is relatively fatigue resistant
muscles and don’t contract as rapidly and strongly; used for aerobic trainings.
Smooth Muscles – muscles that are utilized by a person’s internal organs and
involuntary/automatically performed by the brain and nervous system. (ex. movement of the
intestinal tract)
White Blood Cells (WBCs) – blood cells responsible for protecting the body from foreign
bodies; also responsible for tissue reconstruction in wounds.
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