A transgender athlete who was born a man smashed four women's powerlifting records, prompting gold medal winning Olympian Dame Kelly Holmes to brand the situation a "bloody joke".

Transgender powerlifter Mary Gregory bragged of winning 'nine out of nine' events at the Raw Powerlifting Federation Event while setting new world records for Masters Squat, Open bench, Masters dead lift and Masters total.

"A huge thank you to @raw_powerlifting_federation_, from the bottom of my heart! As a transgender lifter I was unsure what to expect going into this meet and everyone – all the spotters, loaders, referees, staff, meet director, all made me welcome and treated me as just another female lifter- thank you!" said Gregory in an Instagram post.

Former swimming champion Sharron Davies said the situation was unfair to biological women.

"This is a trans woman a male body with male physiology setting a world record & winning a woman's event in America in powerlifting. A woman with female biology cannot compete… it's a pointless unfair playing field," she tweeted.