SHARON Christopher is hoping to swap "pounds for pounds" - by losing five stones during her challenge of a lifetime.

Cycling 400km along the River Nile in five days requires strength, determination and £2,500 in sponsorship. For Sharon, 34, it also requires weight loss.

Mum-of-one Sharon signed up for the task after watching her mother-in-law, Joan, shed a similar amount of weight to cycle around Cuba last year.

Sharon, of Haxby, weighs just over 18 stones and is 5ft 6in tall, but she has abandoned her "coach potato" lifestyle and is out and about on her bike every night.

"I used to be on the "three Cs diet" she said. "I'd joke that every meal I ate would have three things beginning with C in it, like chocolate, cakes, crisps or corn.

"Now everything is low fat and a lot healthier. I used to be a real coach potato, but now I'm out exercising every night."

Sharon hopes to raise £2,500 to improve the health of women and babies. The money will go to the Institute of Obstetrics & Gynaecology Trust's Women For Women appeal to improve prevention, diagnosis and care of women's health problems and those associated with contraception, pregnancy and birth.

In preparation for the event, Sharon is taking her exercise bike to popular York shopping spots to encourage sponsorship.

"Going to Egypt has always been a dream for me, and the beauty of this trip is I can combine it with helping women and babies," she said. "Hopefully I'll be able to swap pounds for pounds before the ride in October."

Sharon will be at McArthur Glen Designer Outlet on March 12, at Monks Cross on April 23 and at Toys R Us in Clifton Moor on May 14.

To sponsor her, log on to http://uk.geocities.com/sharonnchristopher/ or phone 07817 026819.

Updated: 11:30 Friday, February 25, 2005