 Complete the following phrase:  As a teenager, Voronina specialised in the javelin throw and was runner-up at the national championships at the age of fifteen. She represented her country in that event at the 2009 World Youth Championships in Athletics, competing in the qualifying round only. She took up the heptathlon event in 2011 and soon afterwards won the Uzbekistan national title with a personal best of 5287 points. After an absence in the 2012 season she returned to make her senior international debut at the 