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Types of Muscles
Muscles can be divided into two main groups–voluntary and involuntary
muscles.
Voluntary Muscles
These are the muscles that are under our conscious control. They are
attached to the bones. You can control the muscles in your arms and legs
when you run, walk, jump or swim.
Involuntary Muscles
These muscles are not under our control. They work without our thinking
about them. Our stomach and heart have involuntary muscles.
Did You Know?
On an average, approximately 40% of your body weight, is in muscles.
Types of Muscle Fibres
Muscles are made up of cells called muscle fibres. There are
three types of muscle fibres :
Striated Muscle Fibres
All voluntary muscles attached to the bones are made up of
the striated muscle fibres. These are also called the skeletal
muscles. They have dark bands running across the muscles.
Smooth Muscle Fibres Striated muscles
Most involuntary muscles have smooth muscle
fibres which are long and narrow at the ends.
These muscles do not have bands. Organs of
the respiratory and circulatory systems are
lined with the smooth muscles. The smooth
muscles can work for a long time without
Smooth Muscles
getting tired.
Cardiac Muscle Fibres
The heart is made up of the cardiac muscle
fibres. They have bands similar to those found
in the striated muscle fibres. Like the striated
muscles, they work quickly and are powerful. Cardiac Muscles
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