Her early international career saw her secure a bronze medal at the 2006 Lusophony Games, followed by a gold at the same event in 2009. She further demonstrated her rising talent with a silver medal at the 2011 Universiade. Mamona then achieved a significant breakthrough in her senior career, securing a silver medal at the 2012 European Athletics Championships in Helsinki, which also marked a national record. She continued to perform consistently, placing 4th at the 2014 World Indoor Championships and 5th at the 2015 European Indoor Championships.
Her career continued to ascend in 2016, where she won her first major senior title: a gold medal at the European Athletics Championships in Amsterdam, again setting a national record with a jump of 14.58 meters. Later that year, Mamona achieved a sixth-place finish at the Olympic Games in Rio de Janeiro, further improving her national record to 14.65 meters. Her exceptional achievements in 2016 were recognized with the title of Commander of the Order of Merit. Following this, she earned a silver medal at the 2017 European Indoor Championships and placed 9th at the 2017 World Championships, maintaining her competitive edge on the global stage.
Her commitment to elite performance continues, evidenced by her 6th place finish at the 2022 World Indoor Championships and an 8th place at the 2022 World Championships. In the same year, she placed 5th at the European Championships. Most recently, Mamona secured a bronze medal at the 2023 European Indoor Championships. She consistently represents Sporting Clube de Portugal at the club level, solidifying her status as an Olympic silver medallist and a multiple European champion in triple jump.