Rebecca Adlington has been described by her coach as "the best female swimmer in the world".
The reigning 400m freestyle champion will be looking to defend her title when she begins her programme on Sunday evening.
Adlington's coach Bill Furniss said: "I'm biased of course but technically I think she is the best female swimmer in the world.
"She's got this ability to keep a line in the water – nothing deviates, it's very compact, very precise. Most people increase speed by increasing the rate. Rebecca actually increases her speed by lengthening her stroke – her rate can drop, which is uncanny – you don't see that."
"If you were to describe a text book freestyle there is nobody better - male or female. It's perfect, it's everything you want."
Adlington will be competing in the women's 400m and 800m freestyle at the London Olympics.