Very large bowel movements can be caused by hard stools, constipation, eating large meals and other medical conditions.
Constipation can cause hard stools or hard poop and make it difficult to pass and then lead to larger and harder to pass poop or stools.
Eating a large meal can also cause a temporary increase in the size of your bowel movements and if the meal you ate is also high in fiber and water, the poop may be larger and easier to pass.
Other conditions such as megacolon and inflammatory bowel disease can also cause enlarged colons and a larger bowel movement.
Megacolon is a condition in which your colon becomes enlarged due to chronic constipation and or other factors and the enlargement of the colon can lead to larger bowel movements.
Other medical conditions that can cause very large bowel movements are diverticular disease and diverticulitis which can affect your colon and cause changes in your bowel habits and cause larger bowel movements .
And in rare cases colorectal cancer and other GI tumors can cause changes in your bowel habits and larger bowel movements.
And certain medications such as some pain relievers and laxatives can cause larger bowel movements and even stress and anxiety can cause larger bowel movements and impact your bowel functions and also can cause changes in your stool size and frequency of bowel movements.
Feeling like you have to poop but little to nothing comes out can be a result of constipation or pelvic floor dysfunction or even rectal tenesmus or even a partial bowel blockage or impacted bowel.
You can also have bowel blockages and still experience some pooping or even watery diarrhea.
Gastrointestinal conditions can also be a cause of feeling like you want to or needing to poop but not having any poop come out.
Rectal Tenesmus is a feeling of needing to poop even when your bowels are empty or when there's nothing left to pass.
Rectal Tenesmus is often described as a persistent, painful urge to evacuate your bowel, potentially with straining or cramping.
If you continue to experience the urge to poop but nothing comes out and it lasts longer than a week you should see a doctor.
Taking some laxatives and increasing your fiber intake can help in some cases.
Feeling like you want to poop but nothing comes out can be a result of a bowel blockage or simple constipation.
Bowel blockage can sometimes require medical attention if things such as stool softeners or laxatives don't work and constipation most often resolves on it's own.
The amount of weight you can gain from not pooping for 4 days is between 1 to 2 lbs depending on how much poop you have blocked up in your bowels and intestines.
The worst symptoms of constipation are feeling that your rectum is blocked, stomach pain and stomach cramping, the need to use a finger to remove the poop, feeling that your poop has not passed, hard dry or lumpy poop and fewer than three pops per week.
Some people can go up to a week or 8 to 9 days without pooping depending on their diet.