What is the difference between 'anal contractions' and 'rectal contractions' ?
Oops! Better read the Wiki...
anal contractions are the muscles you use to hold back gas, they have a pulling in or closing off sensation.
rectal contractions are the muscles you use when straining as for a bowel movement, they have a pushing out or opening up sensation. If you've ever had a digital rectal exam, the doctor has probably asked you to use this contraction so he/she can get the finger through the involuntary sphincter.
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