Foster has competed at four previous Olympic games
Swimmer Mark Foster is aiming for a first ever Olympics medal in China to add to his 47 international medals.
Foster, 38, will compete in the 50m freestyle having broken the British record in the distance last month with a time of 21.96 seconds.
He told BBC Radio Cambridgeshire: "I want to go faster than I've ever been.
"I'm optimistic but I'm also a realist at the same time. The goals are 'make semi-final', 'make the final' and in the final anything can happen."
Essex-born Foster, who lives in St Neots, said his preparations leading up to the tournament have gone well.
"My event is 21 seconds and if you take the dive off that become 18 or 19 seconds.
"All my training is based around going as fast as possible for 20 seconds as I don't want to last for a minute or 10 minutes," he added.
"The training I do in the gym and pool is very specific to what I will do when I dive in and race at the Olympic games."
The University of Bath swimmer said a medal in Beijing would be the highlight of his career.
I've baked a wonderful cake and it's got icing but if I could win an Olympic medal it would put a cherry on top
"I've achieved so much throughout my career with 47 international medals," he said.
"I've baked a wonderful cake and it's got icing on the top and it tastes delicious and I'm happy with it."
But he added: "If I could win an Olympic medal it would put a cherry on top."