The fitness fan said the photograph and message of the article is important.
"I trained for two months with Dalton Wong to promote a very important message - fit not thin, in Women's Health UK tomorrow. Some very powerful images," the TV presenter wrote on Twitter last night.
The model, who is known for her advocacy of health over thinness, recently said: "If there is one thing I've learned it is that strong is better than skinny."
In her photograph for Women's Health UK she is seen in a Herculean pose as she talks about what a body for life means to her.
Other celebrities who took part in the nude shoot are celebrities Millie Mackintosh, Kimberley Wyatt, Louise Hazel and Tracy Anderson.
Amanda who turned 40 last year said she feels better now than she did at 30.