The abdos are basically involved in all the body motions , to start with the breathing . They work in different ways (endurance , concentric , eccentric, isometric , agonists , antagonist …) and in all directions , the more often as postural controllers but also sometimes as motor muscles of extremely violent movements . Therefore , it’s a good idea to fit yourself with the abdos you need and not necessarily with the ones which look good on the picture , like the well known ”chocolate tablet” of the body builders. A specific conditioning must prepare for all the eventualities and modalities of use. This is not as easy as it looks because of the complexity of the actions and the different roles of the muscles belonging to this group . Also not to be forgotten that the ”abdos” are only a part of the problem which is in fact the full trunk core strength . In this chapter , we are planning to load several videos of known or less known exercises that anyone will be able to pick and adapt to his own use . Available documents : Vid1 ”Crazy abdos” an ”old” video I made some years ago , (not to put in all hands !) …Additional videos with a few examples of variations with different intensity and difficulty. (With Valerie ADAMS , Stephanie WRATHALL and Cie )