I see a lot of people using the hyperextension bench (for lower back) for working out their abs (Roman chair sit-ups, sometimes with weights) and for working out their sides (by going sideways on the bench and doing side-bends). I think both of these exercises are dangerous for your back and don't really benefit your abs. People seem to think they can get rid off their "love handles" by doing side-bends. I think that they only make your waist wider and can hurt your lower back and spine. Could you tell me your opinion please?
For the typical gym member, these exercises are very advanced, especially if the bench you are referring to is horizontal to the floor. It's not that the exercises are bad, it is who is doing them, how they are doing them and when in the training career they do them. These exercises require a lot of core stabilization, meaning that the deep intrinsic stabilizing muscle of the spine, hips and pelvis must be working at their highest ability. If they are not, as is the case with most people in today's society and especially at the gym, these exercises will place a tremendous stress to the structures of the low back. Most importantly, it is not necessary to perform these particular exercises that are probably too advanced when there are many other exercises that would be more beneficial and burn more calories. And as of today, spot reduction has not be proven effective. Always remember, just because an exercise is hard does not mean its good AND just because an exercise is good does not mean its hard.