Muscle Growth


Introduction

With the introduction of such modern conveniences such as the automobile, remote
control, and even the electric toothbrush people are relying on technology to do
everything for them. With a generation growing up in todays society physical
tasks have almost become obsolete. Tasks such as even going shopping and going
out to visit a friend can be done from the comfort of your own computer. With
this sedentary lifestyle, muscular size will almost be unnecessary, except for
the athlete who wants to succeed in sports. To the non-athlete, there will be
no reason to leave the house because everything that you need will be at your
fingertips, you will not have to get up and do anything. Any type of exercise
is good for the body and muscles. Muscle growth is essential if you want to
look better, feel better, and perform everyday tasks such as walking to the car,
and getting out of bed easier. A person who is in shape will also sleep better
then an out of shape person, and feel more revitalized in the morning.

Muscles account for approximently 35% of the body weight in women, and about 45%
of the body weight in men. With over 600 muscles covering the human skeleton
muscles give the body bulk and form. Then human body contains millions of
muscle fibres whose coordinated contraction cause the whole muscle to contract.

Muscles are the foundation on which our bodies are built. Without muscles our
bodies could not perform the simplest tasks such as opening our eyes, talking,
breathing and even the pumping of our heart or the most difficult tasks, such as
running the hurdles in a track and field event.. Muscles are also important to
maintain balance and posture.

Description of Muscles

In the body there are several types of muscles that control different functions
in the body, one of these types being skeletal muscle. Skeletal muscle is the
most evident in the human body due to it having the most mass the other types of
muscles and that it lies directly under the skin attached to the skeleton by
tendons and ligaments.

Skeletal muscles are divided into three structural units, the entire muscle, the
muscle bundle, and the muscle fiber (cell). Each muscle fiber is divided into
two types of fiber structure, fusiform and pennate, with the pennate being
broken up into three basic structures. These structures being the unipennate,
bipennate, and multipennate.

Notice the longditudinal
grain of the
fusiform muscles (left)
compared the
pennate muscles. (below)

Striated muscle tissue (above) is associated with the muscles related to the
skeleton and movement. Striated muscle tissue is the muscle tissue located
directly under the skin and are the muscles that are the most visible.

There are two types muscles in skeletal muscles, these are fast twitch and slow
twitch muscles. Fast twitch muscles have a fast form of myosin ATP and are very
good of delivering calcium to the muscle cell. Slow twitch muscles have a slow
form of myosin ATP and are not very good at delivering calcium to the muscle
cell. Fast twitch muscle fibers reach peak tension more then twice as fast as
slow twitch muscles, making them more explosive muscles which would be more
desirable for athletes such as sprinters.

Notice the dark slow twitch
fibers and the light slow
twitch fibers magnified. The
fast twitch fibers tire
more easily then the lighter
slow twitch fibers.

Causes of Muscle Growth

Muscles growth (hypertrophy) takes place in the muscle fiber themselves. When a
muscle grows there is not a increase in the amount of muscle fibers, since this
is set at birth, but rather an increase in the size of those muscle fibers, and
an increase in the amount of connective tissue in the muscle. Muscle fibers are
enlarged through resistant training, or regular activity by stimulating the
amount of the contractile proteins, actin and myosin. What this does is make
more cross bridges available to do more work.

Muscle fibers with no apparent
resistant training
Muscle fibers with considerably
more resistant
training

The stimulus that tells the muscle to grow is a result of two things, the
shortening of the muscle against a resistance and the intensity of the
contraction. For growth process to start a point must be made in your workout
where the exercised muscle is working near maximal capacity against a resistance,
and the relative intensity of the exercise is very high. When performed just
right, a highly intense resistant exercise disrupts cell wall and cellular
microfilaments, which begins the growth process.

A: General Adaptation Syndrome (G.A.S)

The way our muscles respond to training is the same way that any other stimulus
response mechanism in our body responds to