the smooth muscle
Cardiac
The bicep muscle. The tricep contracts to straighten the arm as the bicep relaxes.
contract
Relaxes
gdg
I think what your after is called an antagonistic pair of muscles, for example the bicep and the tricep. When the bicep is contracting the tricep relaxes and when the tricep is contracting the bicep relaxes.
It Contracts
It relaxes
antagonist.
relaxes
A muscle that contracts shortens whereas a muscle that relaxes lengthens.
false