What two factors are directly affected by changing the speed in which an exercise movement is performed?

The factors directly affected by changing the speed at which an exercise movement is performed are velocity and power output.

When the speed of a movement is increased, the velocity of the movement adjusts accordingly. This change in velocity influences how quickly the muscles have to contract, which in turn affects the power output generated during that movement. Power output is a product of both velocity and the force produced by the muscles. Therefore, as the speed increases, if the muscle force remains constant, the power output will also increase as a result of greater velocity.

Torque, which is the product of force and the distance from the fulcrum, can also be influenced by changes in movement speed, but it is not specifically one of the two direct factors related to the exercise execution speed. Consequently, velocity and power output are the most relevant factors when discussing the impact of speed changes in exercise movements.