The dumbbell spell caster is an exercise that primarily targets the abdominal muscles such as the obliques. However, it also works shoulders, back, hips, and legs, and demands all of those muscles work together in a coordinated motion. It is usually performed with relatively light weights for moderate to high reps, at least 8-12 reps per side. Make sure to only use a weight you can control.
Strengthens the core, including the obliques
Challenges and activates the upper back muscles
Full-body strength and coordination challenge, even with light weights