Five-times Olympic champion Katie Ledecky is focused and improving fast in the run-up to the Tokyo Games, her coach said on Thursday, as she embarks on a gruelling quest for five gold medals to cement her place in swimming history.

Ledecky comes in as the favourite in two of her four individual events in Tokyo but must outshine in-form Australian Ariarne Titmus in three of those to deliver on a clean sweep.

Starting on Sunday, the 24-year-old American will take on the 200, 400, 800 and 1,500 metres freestyle, plus the 4x200m freestyle relay, which could involved at least 10 races in the space of a week, totalling 6.2 kilometres (3.85 miles). Read More