With the intruder on the floor she grabbed a shampoo bottle from the kitchen and poured it “in his face – all of it”.
She said: “I really did a number on that man, I’m serious!”
The burglar may have been looking for an easy target but ended up with a trip to hospital.
Police tweeted a picture with Ms Murphy after Thursday’s incident, saying she was “tough as nails”.
The octogenarian works out almost every day and says she can do one-handed pull-ups and push-ups.
Ms Muphy is an award-winning powerlifter
She also won the World Natural Powerlifting Federation Lifter of the Year award in 2014 and can deadlift more than twice her weight.
Michelle LeBoo – from the YMCA gym that Ms Murphy goes to – said “she really helps dispel the myths of ageing” and called her a “strong beautiful woman” who does things “for the benefit of others”.