Mupopo picked up athletics in the spring of 2014, running 53.44 for 400 metres in her first official meeting. She represented Zambia at the 2014 Commonwealth Games in Glasgow, where she ran 53.09 and was eliminated in the semi-finals. In August, she took silver in 51.21 at the African Championships in Marrakech, breaking the Zambian record; she lost the gold to Nigeria's Folashade Abugan, who ran the same time, in a photo-finish. Mupopo qualified to represent Africa at the 2014 IAAF Continental Cup, also in Marrakech, where she placed fourth and improved her national record to 50.87. Mupopo received an 18-month athletics scholarship from the Zambian Olympic Committee in 2015, leading her to concentrate on athletics and not football.