GLOSSARY

An isometric contraction is one in which the muscle produces force but its overall length and the joint angle do not change significantly, because muscle force equals the external force.
The word comes from the Greek iso, meaning “equal”, and metron, meaning “measure”.

Scientific Note

In an isometric contraction, although whole-muscle length is constant, the muscle fibres shorten slightly and the tendon stretches slightly, so at the sarcomere level movement is not completely zero.

Types

• Yielding isometric: holding a load in a position, such as holding a dumbbell with the elbow at 90 degrees.
• Overcoming isometric: pushing against an immovable object, such as pushing a wall.

Relevance to Sport