These exercises target the calf muscles and promote hypertrophy without stressing the upper legs and growth in that region while giving them the chiseled look.
Leg presses are an excellent way to engage the legs without stressing out the back or any other regions of the body.
Dumbbells are free weights that allow for a more concentrated movement and hence are part of most strength training programs when it comes to building arm strength.
The barbell curl has stood the test of time as a great isolation workout that works both the upper arms and forearms to build strength and stimulate muscle growth in that region.