"I would never in a million years take a drug to help me, so why would I wear a suit just to improve my performance? It’s just not who I am," the Telegraph quoted the 20-year-old as saying of the new drag-reducing impermeable suits.
Adlington is to compete in the 400m, 800m and the 4x200m relay in Italy.
But she insists she wants to win solely through her natural ability rather than resort to technological aids.
"I got into swimming for the love of swimming and I work as hard as I do because I feel I can achieve things, but I don’t want to stand up there on a box and improve just from wearing a suit - I want to improve because of my ability as a swimmer," said Adlington.
"I’ve chosen not to wear it and that is just down to my own morals ... at the end of the day I’ve not compromised my beliefs in any way and that makes me feel better as a person."
Swimwear technology has been increasing apace in recent months and Arlington herself was one of a number of top stars who used Speedo’s friction-reducing LZR Racer suit at last summer's Beijing Games during which 25 new world marks were set.
Swimming's world governing body FINA last month dropped its ban on the lastest new designs amid threats of legal action.
FINA became further embroiled in the suits issue Friday when US swimwear maker TYR failed in its legal bid over the body's list of competition swimsuits approved last month.
FINA published a list of approved suits on June 22 that included the all-polyurethane Jaked01 and a modified version of the part-polyurethane Arena X-Glide.
TYR complained four designs it submitted to FINA have not been approved.
A French court dismissed TYR's action because the matter was outside French jurisdiction with FINA based in Lausanne.
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