23 What is the difference between isometric and isotonic exercises?

Isometric exercises are exercises that are done statically, meaning there is no range of motion while training. The muscles are engaged against a resistance, but do not move. Examples of isometric exercises:

The plank for abs, wall sits (sitting against a wall and holding the position), calf raises in which you remain static at the top of the lift.

Isotonic exercises cause muscles to contract or extend while engaging resistance. This includes bicep curls, push ups, squats, and most other exercises.