Brief Answer:
It's a kind of reflex system of the body

Detailed Answer:
Hello Dear

After reading the medical query raised by you I would like to tell you that all the body process like vomiting, hiccups, sneezing, straining at stools, mild defecation raises sympathetic drive of the body which ultimately leads to slight increase in heart rate and blood pressure which is normal physiological process.

Here I would like to ask you that what's your normal average blood pressure and how much is the increase during defecation process?

Simple measures that you can adopt to avoid constipation includes
1 Avoid smoking completely ( if you do )
2 Drink adequate amount of water daily and keep yourself hydrated
3 Avoid late night eating and stick to a daily schedule specially avoid red meat at night.
4 Include good amount of fresh green leafy vegetables and wholegrain cereals
5 Take a cup of warm milk daily before going to bed

I hope this information will answer your query. I'll at your disposal for your othere queries and doubt

Kind Regards
Dr Bhanu Partap

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