Do boys have a pelvic floor - how would a doctor test to see if it's not functioning? son is not constipated but bm's take an hour to drop out.

Interesting question: Males have the same peri-anal muscle makeup as females.These are designed to signal the brain when stool is ready for emptying and to prevent accidental emptying.Emptying is dependent on donut like muscles in the walls of the large intestines. A chronic pattern of stool retention can balloon the walls and weaken their ability to squeeze.Frequent emptying helps the walls thicken and regain strength.

BM, not pelvic floor: All people have a pelvic floor, but rarely is it a problem in males. The problem you describe is likely an issue of intake; enough fluid intake and enough fiber. Increasing whole grain foods may help. It may also help to add psyllium (metamucil or konsyl). Adding fiber without increasing fluid intake may worsen problem. Should seek doctor visit if problem persists.

Bad habit: This is combination of low fiber diet, little water intake and bad training habits. He should not go and sit in the bathroom unless he is about to pass the bm. No benefit from sitting and wait. High fiber diet during the day with plenty of water will help.