The Dead Bug is a very common exercise used for core training. Most often what we see is a lot of arm and leg movement with very little control of the trunk and pelvis; this is definitely not training the core. This video teaches a progression of movements, starting with setting neutral posture and ACTIVATING the core in a supine 3 or 4-month developmental position. From there, you will how learn to dissociate movement of the hip from the trunk and pelvis. The movements progress in the level of difficulty while challenging the ability to maintain a neutral posture- this IS core training.
Clinic website: https://cloverdalechiro.com