Lejla grew up in Sarajevo, while very young she showed passion for sport and cycling. After intense searching for a mountain bike racing club she started training with Amar Njemčević, one off the best cycling and condition coaches in Bosnia and Herzegovina. After a few years of racing in national races, Lejla started her professional and international career in 2013. She signed a professional contract with Turkish cycling team Salcano Cappadocia in 2014. Lejla won three medals on Balkan championship races, in 2014 she was second in Macedonia and also winning second place in Greece in 2015. But in 2016 she won first gold medal in elite category for Bosnia and Herzegovina on Balkan championship in Montenegro. After that victory she became most successful mountain bike rider in history of Bosnia and Herzegovina. After season 2015 and 2016 where she was riding for Salcano team from Turkey she signed for SMF Team from Greece for season 2017. In season 2017 Lejla Tanovic defend her Balkan champion title in Nafpaktos (Greece), this was her second straight time that she won Balkan title in elite category. In 2018, Lejla defend her Balkan championship title at competition held in Romania