There are two types of muscle contractions: isotonic and
isometric The prefix of both words is iso and it means the same
Different exercises exert different contractions. Isotonic involves
muscle contraction and shortening movement as depicted in the
figure above whereas isometric does not involve muscle shortening
movement but deals with muscle contraction The basics
Slide 4
At the beginning of life, humans exerted isotonic contractions:
infants using their arms to sit up, a pull up bar at a playground
and swinging a bat are all considered isotonic contractions
Exercises are considered isotonic if they meet the following
criteria: an eccentric and concentric phase must be involved. Also,
tension within the muscle must be present, but the joint on the
other hand will have no movement
Slide 5
Isotonic contractions will have the same tone. This means there
is no droopiness and the muscle is toned throughout the entire
exercise
Equal length contractions are considered isometric. If the
muscle is contracted but not shortened, the same, equal length is
maintained The limb will be in a fixed position and no movement
will occur. Tendons will be pulled, but the length will remain
unchanged
Slide 8
Isometric contractions are a convenient way to stay in shape.
Common household/office items such as chairs and walls are perfect
for this type of exercise Even the busiest people can find time to
fit these beneficial, quiet exercises in throughout the day. Always
consult a physician before performing any intense exercises.
Isometric contractions can raise the blood pressure and heart rate
in little time causing danger to some
Slide 9
Chair leg extension Hand press Wall push off Overhead press
Side bend Neck stretch Cross arm stretch Arm flex