U.S. Marines with the 15th Marine Expeditionary Unit and the French 5th Overseas Combined Arms Regiment (RIAOM) perform crunches as part of indoctrination prior to participating in a desert survival course. Elements of the 15th MEU are training with the 5th RIAOM in Djibouti in order to improve interoperability between the MEU and the French military. - U.S. Marines with the 15th Marine Expeditionary Unit and the French 5th Overseas Combined Arms Regiment (RIAOM) perform crunches as part of indoctrination prior to participating in a desert survival course. Elements of the 15th MEU are training with the 5th RIAOM in Djibouti in order to improve interoperability between the MEU and the French military.