In May 2012, Arenas won the women's 10 kilometer event (junior event) at the 2012 IAAF World Race Walking Cup in Saransk, Russia. In July 2012, Arenas won the bronze medal in the 10km race walk event at the 2012 World Junior Championships in Athletics with a time of 45:44.46. Arenas placed 32nd in 20km race walk at the 2012 Summer Olympics with a time of 1:33:21. She Again Placed 32nd at the 2016 Summer Olympics, with a time of 1:35:40; She went on to Place Second in the 2020 Summer Olympics, with a time of 1:29:37.