Study Subject
A 24-year-old female healthy volunteer was recruited through local advertising. The participant gave written informed consent and all procedures were approved by the Hamilton Integrated Research Ethics Board (HiREB). Exclusion criteria were abdominal surgery, hepatic, kidney or cardiac diseases, connective tissue disorders, central nervous system disorders, thyroid diseases, prostate diseases or malignancies. The subject had normal stool consistency and normal bowel frequency, between 1 every 3 days and 3 per day. The subject had no defecation difficulty and was not taking any medication.