Denise Van Outen says her feet have become so painful during Strictly Come Dancing rehearsals she has to practise barefoot.
The star - who was paired with professional James Jordan at the weekend - said she is so sore she has been unable to even get her shoes on.
Denise also said she had been upset by suggestions that she had an advantage over her show rivals with her background on the stage in productions such as Chicago.
"This competition is not musical theatre, it is ballroom, and this is a world that I am in no way familiar with," she said.
Writing in an online blog, she said: "I feel that I'm at a slight disadvantage this week as my feet are so badly blistered due to dancing in heels, that I can't even get my shoes on and I'm having to practise barefoot until they heal.
"Even so, I wouldn't change a thing as I'm loving every minute of it."
Denise faces 13 other celebrities in the BBC One dance series and is preparing for the first live show which takes place in early October.
She said: "I have to say that I was quite upset at the criticism that I've come under from the press about my involvement with the show due to my previous dance experience.
"I would like to take this opportunity to express that I have danced at theatre school as part of my training, and I did appear in the musical Chicago where I had one dance number, but apart from that, my dance experience is very basic, and secondly, I am not the only competitor that has appeared in the show that has had basic training.
Denise also told how she had to keep her involvement in the programme under wraps: "The lengths that I've had to go to, to keep it secret were unbelievable. With any correspondence in regards to the show such as emails and meetings, I was never allowed to mention the word 'Strictly'. I always had to refer to my new job as 'legal', which was also my code name for the show."
