Muscle is a soft tissue in the body of humans and animals.
Its main purpose is to produce force and motion.

Muscles are responsible for maintaining posture, physical
movement (sitting, walking, eating, etc), and movement of internal organs (such
as keeping the heart pumping to circulate blood and moving food through the
digestive system).

The word muscle is derived from the Latin term musculus,
meaning “little mouse”. This Latin term could be due to the shape of
some muscles or because muscles contracting under the skin can look like a
mouse moving under a rug.

Tendons connect our soft contracting muscle to our hard
bones.

There are around 650 skeletal muscles in the human body.

There are three types of muscle, skeletal, cardiac, and
smooth.

Skeletal muscles (or striated) are voluntary muscles that
control nearly every action a person intentionally performs. Tendons attach the
muscle to two bones across a joint, as one muscle contracts the other relaxes
which moves the bones.

Skeletal muscle can be further divided into two types, slow
twitch and fast twitch.

Slow twitch (Type I) muscle contain proteins that give it a
rich red color. This muscle carries more oxygen efficiently and using fats,
proteins or carbs as energy slow twitch muscle fibers contract over a long
period of time.

Therefore type I muscle fiber works well for aerobic sports
such as long distance running and cycling.

Fast twitch (Type II) muscle is whiter in color as it has
less myoglobin (a oxygen carrying protein). Fast twitch fibers contract quickly
and powerfully, however they fatigue rapidly.

Therefore type II muscle fiber is useful for anaerobic
exercise such as sprinting or for strength sports like weightlifting.

Smooth muscle (or visceral) is involuntary, its not
controlled by our conscious mind. It is found on the walls of many organs and
structures such as the esophagus, stomach, intestines, bladder, and blood
vessels. Smooth muscles contract to move substances such as food through the
organ.

Cardiac muscle is also an involuntary muscle. It is only
found in the heart and is responsible for keeping the heart pumping.

Muscle makes up around half of the total human body weight.
Muscle tissue is also around 15% denser than fat tissue.

It takes 17 muscles in the face for us to smile and 43
muscles to frown.

If muscle strength is regarded as the ability to use force
on something then the jaw muscle (masseter) is the strongest in the body.

The strongest muscles in relation to the job they have to do
is the external muscles of the eye which are large and about 100 times stronger
than they need to be in relation to the small size and weight of the eyeball.

The tongue has 8 muscles, so is technically not the
strongest muscle in the body.

The heart cardiac muscle does the most work of any muscle
over a lifetime.

Cerebral palsy is a disorder that affects balance and motor
functions, while muscular dystrophy is a genetic disease that damages muscle
fibers.

Muscle memory is created by practising an action over and
over again. Our muscles fine tune themselves, becoming more precise and exact
in what they do. So practice is very important when learning a sport!!