​Pushing muscles hard against an immovable object is an example of _____ exercise.

A) ​aerobic
B) ​anaerobic
C) ​isokinetic
D) ​isometric

Isometric

Pertaining to exercises or muscle actions where the muscle length does not change during contraction, often used for strength training.

Isokinetic

Relating to or denoting muscular action in which the length of the muscle changes at a constant rate while under constant tension.

Anaerobic

Describes processes or organisms that do not require oxygen for growth or survival.