As referred to in the literature, patients complaining of constipation may have a spastic or, in the case of chronic staining, weak pelvic floor. Twenty-two severely constipated patients who did not improve after a high fiber diet were submitted to whole gut transit time (TT), proctographic, and anorectal manometric studies. A control group consisting of five subjects for TT, five subjects for proctogram, and ten subjects for manometry was also studied. Transit time was delayed (P less than 0.001) in all patients. Manometry in the constipated group showed a high rectal threshold (64.1 vs. 17.1 ml of air, P less than 0.01), but no other significant difference. Proctograms in 10 of 22 patients (Group A) showed no differences in the anorectal angle (ARA) and in its distance from the pubococcygeal line (DLPC) in respect to the control group; 12 of 22 patients (Group B) had a paradoxical closure of the ARA at straining in respect to resting position (101.2 degrees vs. 120.1 degrees), and a higher DLPC than Group A and the control group in all positions studied. There was no difference in TT for rectal stasis of radiopaque markers between the two pathologic groups. Patients in Group B were older than patients in Group A (55.3 vs. 42.9 years, P less than 0.05). In conclusion, proctograms showed alterations of the pelvic floor, but there was no correlation between protographic data and rectal or colonic stasis of the radiopaque markers, or clinic severity of constipation, but a correlation between ages did exist.