Austrian rower Leo, father of Dieter Losert, partnered Viktor Flessl in the double sculls at the 1928 Amsterdam Olympics and won the bronze medal. Both won the German nationals in 1926 and 1927 and were runners-up in 1925 and 1928. In 1925, Losert also won silver at the German nationals in the single sculls.
Losert became a graduated lawyer by profession and regularly worked as a rowing coach. In 1964 and 1968 he coached the Austrian national team at the Olympic Games. Among others he coached his son Dieter.