exercise

Neither, honestly these things are less effective than doing simple exercises such as crunches and hanging leg lifts. the reason is these machines make the exercise easier for your body which means your body will not build ab muscles as quickly. something ton consider is if your looking to see your abs and not to thicken them is many big actors such as Brad Pitt have been known to not do abs workouts at all, after all we all have them, most peoples abs are simply hiding under a natural layer of body fat.