Greg Walker, a 7ft tall basketball star, is undergoing a sex change and will become the world’s tallest transsexual.

Greg Walker, now 25, grew up sports-mad with beautiful cheerleaders on his arm, but said he “always felt different”.

Strapping teenager Greg Walker – who has size 16 feet and weighs around 20 stone – regularly lifted weights and would ride motorbikes to mask his true feelings.

The basketball had dozens of girls chasing him but shunned their advances, preferring to become friends instead and discuss fashion and “girly’ things.

In his early 20s, Greg Walker – now Lindsey – was unable to continue the “charade” and began wearing women’s clothes.

He then sought medical advice and began taking oestrogen to become more feminine and now boasts a curvy woman’s body – and a 38B bra size.

Now legally recognized as female after living as a woman for two years, Lindsey said: “I was one of the popular kids in high school.

“I was smart and always had girlfriends and loads of girls chasing me. But it somehow didn’t feel right, almost like it was a charade.

“I started to feel really isolated as thought here was something wrong with me and at 18 I started doing research secretly into why I was feeling so different from everyone else.

“Although I hid my feelings well I lived my life always knowing there was something different. By 21 I had hit my rock bottom and I started having emotional problems and turned to drink.

“Then one day it just clicked and I knew what I had to do. I started wearing women’s clothes and later turned to female hormones to suppress the testosterone in my body.”

Greg Walker, a 7ft tall basketball star, is undergoing a sex change and will become the world's tallest transsexual

Lindsey Walker, from Ohio, grew up as Greg and experienced a “normal boyish” childhood as a keen sportsman and gifted basketball player.

He was offered a basketball scholarship to study economics and marketing at Central Michigan College, but dropped out aged 21.

Greg Walker became increasingly isolated and changed his name from Greg to Lindsey. Lindsey then poured her heart out in a letter to her supportive parents explaining she had always felt and wanted to be a woman.

The acceptance gave Lindsey the confidence to start wearing women’s clothes and undergo a course of female hormones to become more “womanly”.

Lindsey now proudly boasts a B-cup bra size and buys her fashionable clothes and high-heeled shoes to fit her size 16 feet from specialist websites online.

She is legally classified as a woman and is now saving up for full gender reassignment surgery, which she hopes to have by the end of the year or early 2013.

Her supportive parents have accepted her decision although Lindsey is estranged from her younger brother. She has also contacted the Guinness Book of Records in the hope she will be officially recognized as the world’s tallest transsexual.