Like with a barbell, training with dumbbells demands a certain level of intramuscular coordination to activate the main muscle, as well as intermuscular coordination, which involves the other muscles around that joint.
When a person lacks the preparation to perform an exercise or uses excessively heavy dumbbells, they automatically reduce the range of motion to bear the weight. This way, the muscle ceases to be worked in the appropriate manner, hindering results.
Despite the equipment being used in leg workouts, it ends up allowing the student to support more weight, as it is supported on the back, while dumbbells need to be held with hands.
The exercises performed with dumbbells also require closer supervision from the physical education teacher to prevent accidents, such as the accessory falling on the face or feet, as well as incorrect movements that may cause injuries.