Quite often, constipation is due to difficult evacuation. The longer stool remains in the rectum, the worse the situation: fecal matter becomes drier and evacuation becomes even more difficult.
The principal causes of constipation, at whatever age, include: inappropriate lifestyle choices (dietary imbalance, inadequate intake of water, fruits, and vegetables, insufficient physical activity and a sedentary lifestyle), changes in personal habits or climatic conditions (for example, when travelling), use of some drugs, gastrointestinal tract or metabolic diseases (for example, irritable bowel syndrome), or particular conditions such as stress immobility, and confinement to bed (especially in the elderly).
We recommend discussing the problem with your physician, especially in case of persistent constipation, blood in the stool or black, tarry stool, frequent urges to empty the bowel not followed by a bowel movement, abdominal pain, either persistent or of recent onset, constipation alternating with soft stools for a period of weeks or months (if not already reported to your physician).
In some cases, constipation may also manifest as a sensation of incomplete bowel evacuation, despite normal frequency, or the need to strain in order to defecate.