How do isotonic exercises differ from isometric exercises?

Isotonic exercises are characterized by muscle contractions that produce movement, allowing the muscles to shorten and lengthen through a range of motion. This type of exercise is typically associated with activities like lifting weights or performing bodyweight movements, enabling the joints to move along with the muscles. This movement results in the dynamic application of force that builds both strength and endurance.

In contrast, isometric exercises involve muscle contractions that create tension without any accompanying movement at the joints. During isometric exercises, the muscle generates force, but its length remains static, which means there is no change in position or movement in the exercise. An example of isometric exercise is holding a plank position or pushing against an immovable object.

These fundamental differences in movement and muscle contraction types underscore why isotonic exercises involve movement, while isometric exercises are defined by sustained tension in a stationary position, making option C the accurate distinction between the two.