The aim of this monocentric, prospective, non randomised study with 25 healthy volunteers is to assess anorectal function ( i.e rectal compliance and sensory thresholds) in health with a short protocol barostat versus conventional procedures (i.e. standard barostat protocol and high resolution anorectal manometry). Anorectal dysfunction is a key mechanism in the development of fecal incontinence and symptoms of obstructive defecation.