In most fitness facilities, selectorized machines are staples because they are one of the safest modalities, and spotting is not required. Cables and pulleys limit users' direct contact with the weight stack as it moves, and selectorized equipment does not require transporting weight plates to a barbell or weight horn. Enhanced safety and ease of use make selectorized equipment an ideal option for any exerciser. One limitation may be that selectorized machines are designed to fit the average-size user. Although seat heights can be adjusted, some extremely tall or short individuals may not feel as comfortable on some machines and may require extra attention to ensure correct alignment.
Resistance is applied by placing Olympic plates on weight horns on the machine's movement arms.
Although popular among serious athletes, plate-loaded equipment is appropriate for all levels of exercisers. This can enable exercisers to enhance strength gain, or conquer a strength plateau. Because these machines can accommodate very heavy weights, they are ideal for training power athletes, such as football players. Some plate-loaded equipment also features independent movement arms, allowing exercisers to move one limb at a time, both limbs simultaneously or alternate between limbs for greater variety. This independent arm movement additionally enables exercisers to protect an injured limb by using little or no weight on the injured side while maintaining strength gains on the unaffected one.