You get goosebumps when you poop because the physical exertion involved can activate your sympathetic nervous system, the part of your body responsible for "fight or flight" responses.
The Role of the Sympathetic Nervous System
The sympathetic nervous system controls many involuntary bodily functions, including:
- Heart rate: Increasing it during exertion.
- Blood pressure: Raising it to provide more oxygen to muscles.
- Digestion: Temporarily slowing it down.
- Pilomotor reflex: Causing the tiny muscles at the base of each hair follicle to contract, resulting in goosebumps.
Physical Exertion and Bowel Movements
While typically associated with stress or fear, the sympathetic nervous system can also be triggered by physical exertion. Straining during a bowel movement, even if minor, can be enough to activate this system. This is because the vagus nerve, a major component of the parasympathetic nervous system (responsible for "rest and digest"), is stimulated during bowel movements. Sometimes, this stimulation can briefly activate the sympathetic nervous system as well.
Other Possible Causes
It's also worth noting that goosebumps can sometimes occur for seemingly no reason at all. These spontaneous occurrences are generally harmless. However, if you experience goosebumps frequently and they are accompanied by other symptoms, it's best to consult a doctor.
In summary, while the exact reason for experiencing goosebumps during bowel movements isn't fully understood, it is likely related to activation of the sympathetic nervous system due to physical exertion and stimulation of the vagus nerve.
