ANAL INCONTINENCE: CAUSES, HOW POOPING WORKS, AND HOW PELVIC FLOOR THERAPY HELPS
Accidentally leaking stool, gas, or mucus can feel deeply embarrassing. Many people live with it quietly, assuming it is just something they have to tolerate. The truth is that anal incontinence is far more common than most people realize, and in many cases, it is treatable.
Anal incontinence refers to the involuntary loss of solid stool, liquid stool, gas, or mucus. Continence is not controlled by one muscle or one system. It depends on a coordinated relationship between pelvic floor muscles, anal sphincters, nerves, rectal sensation, stool consistency, gut motility, and cognitive awareness. When any part of this system is disrupted, leakage can occur.
Understanding how pooping works is the first step toward improving bowel control.
The Muscles That Keep Poop In
There are three key muscles involved in anal continence: the internal anal sphincter, the external anal sphincter, and the puborectalis muscle.
Internal Anal Sphincter
The internal anal sphincter is made of smooth muscle, similar to the muscle that lines blood vessels. It is under involuntary control, meaning you do not consciously contract it. At rest, this muscle stays contracted most of the time to keep stool from leaking out when you are not trying to poop.
External Anal Sphincter
The external anal sphincter is skeletal muscle, similar to your biceps. This muscle is under mostly voluntary control. It is the muscle you squeeze when you try to hold in gas or prevent leakage during coughing, sneezing, lifting, or sudden movements. It provides an extra layer of protection when abdominal pressure changes.
Puborectalis Muscle
The puborectalis is part of the deeper pelvic floor muscle group called the levator ani. This muscle wraps around the junction between the rectum and anus and creates a natural bend in the rectum. You can think of it like a gentle kink in a garden hose. This bend helps keep stool in place when you are upright and moving around.
When it is time to poop, the puborectalis relaxes and the rectum straightens. This allows stool to pass more easily.
What Happens When You Feel the Urge to Poop
When stool moves into the rectum, the internal anal sphincter relaxes slightly and allows a small sample of what is inside to enter the anal canal. The anus has highly sensitive nerve endings that can distinguish between gas, liquid, and solid stool.
If the contents are solid, reflexes kick in. The external anal sphincter tightens while the internal sphincter continues to relax slightly. If it is not a good time to go, the internal sphincter contracts again to support continence.
This entire process depends on healthy nerve signaling, adequate rectal stretch capacity, and coordinated muscle function. If sensation is impaired, muscles are weak, or timing is off, the system breaks down.
Common Causes of Anal Incontinence
Anal incontinence rarely has a single cause. It is often the result of multiple contributing factors.
Common causes include obstetric trauma, such as injuries from vaginal delivery, especially with forceps, vacuum, or tearing. Surgical trauma, including hemorrhoidectomy or colorectal surgery, can affect sphincter integrity and nerve supply. Radiation therapy can damage tissues and nerves over time.
Neurological conditions such as stroke, multiple sclerosis, Parkinson’s disease, spinal cord injury, diabetes, and dementia can disrupt sensation and motor control. Aging related muscle atrophy can weaken the pelvic floor and anal sphincters. Inflammatory bowel disease, chronic constipation, chronic diarrhea, rectal prolapse, and rectocele can also contribute.
Many people are surprised to learn that constipation is a major risk factor. When stool becomes hard and impacted, liquid stool can leak around the blockage. This is known as overflow incontinence and is often mistaken for diarrhea.
Stool Consistency Matters More Than You Think
Healthy bowel control depends on stool consistency. Ideally, stool should be soft, formed, and easy to pass. This is typically a type 3 or 4 on the Bristol Stool Chart.
If you are alternating between diarrhea and hard pellets, constipation may still be the underlying issue. Signs of constipation include straining, bloating, passing small hard stools, infrequent bowel movements, a feeling of incomplete emptying, and leakage around stool.
Working with a qualified nutrition professional can help normalize stool consistency through individualized fiber therapy, hydration strategies, and dietary adjustments. Fiber, water intake, and vegetables all play an important role, but there is no one size fits all solution.
Toileting Posture and Technique
How you sit on the toilet matters. Using a footstool to elevate your knees above your hips helps the puborectalis muscle relax. This straightens the rectal angle and allows stool to pass with less strain.
Equally important is how you breathe and push. Toileting is not the time to multitask or rush.
When you sit down, take a slow belly breath in and allow your abdomen and pelvic floor to gently expand. As you exhale through pursed lips, allow stool to pass without force. If you need assistance, gently engage your abdominal muscles while maintaining a relaxed pelvic floor. This should feel like a gentle nudge, not a forceful push.
Chronic and excessive straining increases pressure on the pelvic floor and can worsen symptoms over time.
Pelvic Floor Muscle Training for Anal Incontinence
Pelvic floor therapy is a conservative and effective treatment option for anal incontinence. Before starting any exercise program, it is important to be evaluated by a qualified pelvic health therapist who can assess strength, coordination, relaxation, and timing.
In many cases, anal incontinence is associated with pelvic floor muscle weakness, delayed activation, diminished pelvic floor muscle endurance and coordination, changes to rectal compliance, and stool consistency issues.
Endurance Training
To improve endurance, gently contract the anal sphincter and pelvic floor muscles as if you are holding in gas. Continue breathing normally. Hold the contraction for up to ten seconds, then fully relax for ten seconds. Work up to ten repetitions.
Speed and Power Training
To improve quick response, contract the pelvic floor muscles strongly and quickly for two seconds, then fully relax for one second. Repeat ten times.
These exercises should be practiced in different positions, including lying down, sitting, and standing. Over time, they are integrated into daily activities that challenge continence.
Rectal Balloon Training
Pelvic health therapists may use rectal balloon training to improve sensation and control. This involves a thin catheter with a small balloon that is gently inflated inside the rectum to simulate the presence of stool.
For some people, rectal sensation is reduced, meaning they do not feel stool until it is too late. Balloon training helps improve early warning signals. For others, the rectum is hypersensitive, creating urgency when the rectum is not actually full. Balloon training can help normalize sensory thresholds and reduce false alarms.
Intra-Anal EMG Biofeedback
Instrumented biofeedback provides real time information about pelvic floor muscle activity. A small rectal sensor measures muscle activation and displays it visually or auditorily.
Biofeedback helps identify whether muscles are contracting when they should relax or failing to activate when needed. It is particularly useful for improving coordination during defecation and strengthening exercises.
In some cases, therapists use biofeedback during simulated bowel movements to ensure the pelvic floor muscles are relaxing appropriately rather than tightening.
There Is Help and There Is Hope
Anal incontinence can significantly affect quality of life, confidence, and emotional well being. Many people delay seeking care because of embarrassment or the belief that nothing can be done.
Education, proper evaluation, and pelvic floor therapy can make a meaningful difference. With the right approach, many people experience improved bowel control, reduced urgency, and greater confidence.
If you are experiencing bowel leakage, know that you are not alone and that conservative, evidence informed options exist.
This information is not intended to substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of a healthcare professional with any questions you may have regarding treatment, medications/supplements, or any medical diagnoses. This information is intended for educational purposes only and is in no way to substitute the advice of a licensed healthcare professional.
