Just a bit more background on my particular set of circumstances:
Since my constipation was due to medication, nothing helped until I stopped the medication. I had years to experiment with laxatives and the like. My inclination as an otherwise healthy person was to eat well and exercise regularly. What I found is 'at best' I would experience 8-20 days of marble-sized 'pellet' poop (some of which invariably stayed stuck in my rectocele until I manually removed it) interspersed with an occasional 'miracle day' of a pretty ordinary (but occasionally runny) poop. I thought I might have mild Chron's disease but my symptoms didn't fully match. But my point is - whether I hiked, biked, ran, played tennis, whether I ate salads and high-fiber vegetarian all week, whether I fasted or ate steak - NOTHING altered the pattern - Until I stopped the anti-depressant. My constipation eased immediately when I began tapering off that medication. Now that I'm 100% medication free I have wonderfully 'average' bm's again! Instead of every week or 2, I poop every day! And no more 'pellets', but normal consistency.

Medication can be literally life-saving. But constipation is no small matter as a side-effect. I wish biochemists or whoever creates these drugs would take this side-effect more seriously - especially when it can create conditions requiring surgery! Throwing more drugs eg stool-softeners on top of the problem is not imo a solution.