Alessia was born in Rome on 30 June 1992 and began freediving after being a competitive swimmer in her childhood. She started her freediving career when she was 13 years old. In 2006, she took her first course of federal apnea in the Apnea Blu Mare society. Based on the rules, she had to wait until she was 18 to officially compete. She won a silver medal in her debut when she was 18 years old in the Italian Championship. She is the current AIDA world record holder in CWT with an astonishing 104 meters and CMAS world record holder in DYN with 250 meters.
She is currently the "deepest woman in the world" with her -105 meters CWT (Monofin) reached in San Andres Island in 2018. She reclaimed this record which she briefly lost to Hanako Hirose days before, on 10 May 2017.