"Detox and shape up in your bath" is what the box said. With a sell like that, who can resist? Not me, that's for sure. But one thing was worrying me. By rights I am a shower person, but that's in an everyday, always-running-late sort of way. Baths are where I chill out and, while I can't deny the appeal of doing something healthy without lifting a finger, the idea of having to exercise in the bathroom is tantamount to swearing in church.

The Bathrobics beauty spa promises to be "a fabulous bathroom beauty workout to destress, detox and tone, all in one".The starter pack (£16.99, bathrobics.com) contains a waterproof illustrated book (with a rubber sucker to hang over the edge of the bath), a CD, and four thalassotherapy beauty treatments (face mask, body mask, body polish and bath soak). As anyone who has ever attempted the indignity that is water aerobics will testify, exercising in water is harder than it looks. However, while you may feel a fool in the swimming pool, at least you are in good company. Sitting in the bath following an exercise routine makes you feel you are totally isolated in your dementia. It doesn't matter if it works, you feel so darn stupid that your self-esteem plummets - and what's the point of exercise if not to build up your self-esteem (um, apart from all that adding years to your life stuff, obviously)?

But the main problem I had with this kit is that, while I don't doubt the exercises work, I can no longer walk into the sanctuary that used to be my bathroom without feeling guilty. I eye up my wash basin and wonder if I should be doing thigh raises, as per instruction. I sit in the bath and contemplate stomach crunches, when I should be contemplating, well, nothing, other than whether or not I can be bothered to add more hot water.

The kit is like those exercise experts who tell you to do buttock clenches while waiting for the bus. There is a time and a place for everything, and my bathroom is where I pamper myself, not where I exercise, and never the twain shall meet.