Elizabeth Cann is the leading women's singles player in Britain at the moment but the competition is very strong on the world stage.
Cann turns 30 in March, but has never been to an Olympic Games so could keep pushing until London 2012.
"Ladies' singles is so hard with the number of strong Asian players and the world number one, Tine Rasmussen from Denmark," says Emms.
"Elizabeth is fit but she needs to get a lot stronger because her opponents smash a lot harder."
Emms gave up singles at the age of 18 but wishes she had continued, and hopes youngsters will try the format.
"Because we've had so much success in doubles, youngsters want to try that but I keep trying to tell them to play singles too," she says.
"The style of doubles suited me because of my height but playing singles could have helped my game, made it more well-rounded and given me different options."
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