The record-breaking 21-year-old is endearingly bashful about her remarkable rise to the top ranks of a male-dominated career.
Fife-based Alexander appears uncomfortable with the countless compliments her achievements have attracted, preferring instead to concentrate on her riding, and let the horses do the talking.
Her meteoric rise has seen her ride 38 winners last season, including 11 for Barry Murtagh, five for Bruce Mactaggart, five for Ferdy Murphy, and four for her Dad.
"I didn't set any targets at the start of the season because I wasn't sure what kind of support I was going to get," she says.
"The aim was just to do as well as possible but what's happened has exceeded all my expectations."
Since turning professional in September 2011, Lucy has made a huge impact on National Hunt racing, breaking Lorna Vincent's 1980 record of 22 winners for a female jockey in a British jumps season.
That milestone was achieved in February 2012 at Musselburgh when recording her fourth course success on the Bruce Mactaggart-trained Red Tanber, one of her Cheltenham Festival rides.
"She's one of the best up-and-coming jockeys I've seen in a long time," said the Hawick handler.
"A lot of those riding are either good jockeys or good horsemen, but she's both," he added.
"She's also very focused and very professional."
His sentiments are echoed by top trainer Ferdy Murphy, who has also been hugely supportive of her talents.
"Every now and then, a young jockey comes along who stands out above the rest," said the North Yorkshire trainer. "She's the best young rider I've seen for quite a while."
"Jockeys have either got it or they haven't — and Lucy has definitely got it," he concluded.
Before embarking on her chosen path, Lucy had two abortive attempts at student life.
In 2008, she began a biology course at Edinburgh University, and later returned to study sports science.
"I lasted about six weeks both times but it just wasn't for me. I just didn't have the interest in the subject to be doing that for four years," says Lucy.
A clearly intelligent young woman, Lucy left Kilgraston – the only Scottish boarding school with equestrian facilities – with an impressive five As at Higher.
"You can always go back to university and I've got the grades from school. But I'd say I'd always do something in racing," continued Lucy.
Lucy was just five years old when she started riding ponies, and by the age of 12 had progressed to her first racehorse. By 14, she was riding out regularly at her father's yard. Her first point-to-point ride, aged 16, fuelled her desire to become a jockey.
"I rode my dad's horse, Wiseman, who was a great jumper and a brilliant schoolmaster. After winning our first three races, there was no way back," she laughed.
Lucy's first winner under rules was also for her father, when 40-1 chance Seeking Power won at Kelso in February 2010.
An invincible athlete at school – unbeaten in every event from 100m to the shot putt – Lucy has proved equally competitive on the racecourse.
"The thing that always marked Lucy out is that she is ferociously determined and competitive," explained her father, Nick, who trains at their Kinneston home.
"She never gives up," he added.
Lucy is indebted to the constant support she receives from her parents Nick and Rose, and the rest of her family.
In her early days as an amateur, Lucy gained valuable experience working for top flat trainers Aidan O'Brien, Kevin Ryan and Sir Michael Stoute, where she rode with a number of top jockeys including Kieren Fallon.
She says some 20 rides on the flat, including Epsom and Ascot, helped to make her "sharper and tighter" in the saddle.
Lucy's decision to turn professional wasn't taken lightheartedly, and she has proved totally committed – racking up an unenviable mileage travelling to courses across the country.
"It was a big decision to make because I wasn't sure if I'd get many rides," she admits.
"But I wanted to give it a go and I always told myself I could go back to studying if it didn't work out or I get badly injured, but if that happens, it happens. I know that at some point I'll have a bad fall because it's just part of the job, but I can't go around worrying about it because if I was I wouldn't be in the right job," added Lucy.
"I haven't regretted the decision for one minute. I'm delighted with the way things have gone, in particular the number of trainers who have given me rides."
Lucy has never looked back since her decision to turn professional, and sees no disadvantage in being one of the few female jockeys in a male-dominated sport.
"There's a perception out there that people are reluctant to use female jockeys for fear of them getting hurt, but it's not something I've personally encountered.
"I'm aware of the dangers involved, but my attitude is that it's down to luck whether you get injured or not. It's the same for all jockeys – there's no greater risk because you're a girl.
"Trainers like Ferdy Murphy and Barry Murtagh have been really supportive – last season while I was still an amateur Barry gave me plenty of rides against professionals, which is unusual. I've not had any problems with being a girl.
"People ask whether I get fed up being treated as a girl jockey, but it doesn't annoy me because I am a girl jockey! As long as I'm respected for my achievements and treated on merit rather than people saying, 'oh she's good for a girl', then I'm happy.
"But the only way to make sure that doesn't happen is to win races and earn people's respect," she adds.
Gee Armytage was the most successful female professional of recent times, having ridden two winners at the Cheltenham Festival in 1987, and her mother-in-law Sue Bradburne recently announced her retirement from a 24-year long training career, to join Nick Alexander as assistant and consultant.
Sue describes Lucy as "a natural" with "a real racing brain.
"She's got that marvellous natural ability without a care in the world," said Sue. "She just rides with her heart."
Horses and racing have always been a part of Lucy's family life – her uncle Jamie and brother Kit both proving successful amateur riders, while a race at Kelso is named in memory of her grandfather, Cyril.
Lucy is clearly dedicated to her profession – health and fitness being something she treats very seriously.
"Fitness is so important because if you get tired in a race then your brain goes too," she explains.
"People don't appreciate just how physically demanding jump riding is, but I'm lucky because I don't struggle with my weight like some of the lads, who have to waste and be in the sauna every day.
Jockeys' agent Richard Hale is delighted to have Lucy on his books and comments:"Lucy has still got a lot to learn, but one of the good things about her is that she takes advice on board and uses it constructively.
"She's also a very nice, down-to-earth person and that's a great asset too. Owners and trainers enjoy dealing with her and she's also well liked in the weighing-room."
Lucy got the new season underway with a winner at Sedgefield on May 1, winning the 3m 3f handicap chase on Mansonien L'As for Ferdy Murphy.
Lucy, in typically unassuming style, merely adds: "I'm enjoying it so much – I get paid to do something I would do for fun!"