Navy SEAL leg levers Vs Leg Raises

[whut_cohen]

I am currently using Stew Smith's Complete Guide to Navy SEAL Fitness. I'm not following the workout exactly as I don't have access to the sea or a pool for swimming. I just do his PT workouts and run on alternate days. I was wondering if the leg levers and flutter kicks (if anyone is familliar with these exercises) should be treated as leg raises and left until I am accomplished at situps or if they can be treated like situps? I suspect they are not as strenuous as leg raises and can be done along with situps (having tried them) but I would appreciate the opinion of someone more experienced than myself. Mr Kurz if possible.