Balloon Inflation in Biofeedback

The primary outcome measure for this study is the change in anorectal pressure gradient (the difference between rectal and anal canal pressures) recorded during the push manoeuvre on high-resolution anorectal manometry (HRAM). This measurement reflects how effectively the rectal and anal muscles work together to open the bowels - known as defecatory coordination.

The study will compare each participant's average pressure gradient when performing push manoeuvres:

• with the balloon deflated (standard practice), and
• with the balloon inflated to the level that gives the natural sensation of needing to open the bowels.

An improvement in the pressure gradient (i.e. a higher rectal pressure relative to anal pressure) will indicate better defecatory performance.

The secondary outcome measures for this study focus on participants' experiences and perceptions during the biofeedback session, as well as the consistency of their physiological responses.

• Patient-perceived ease and naturalness of the push manoeuvre

• Participants will rate how easy or natural it felt to perform the push manoeuvre under each condition - with the balloon inflated and deflated.
• Responses will be collected immediately after the procedure using a short, structured questionnaire (e.g. Likert-type scale).
• This will help determine which condition feels more realistic and comfortable to participants.
• Reproducibility of defecatory pressure patterns

• The consistency of push manoeuvre pressure profiles will be compared between the inflated and deflated balloon conditions.
• This will assess whether balloon inflation improves the reliability of muscle coordination during repeated attempts.