Former Luton schoolboy and sports supremo Professor Greg Whyte has been coaching Little Britain star David Walliams (left) for a secret project.  The pair have been spotted emerging in wetsuits from rivers, swimming pools and beaches across the country. 

But Greg's lips are sealed - for now - about what they're trying to achieve.  The ex-Ashcroft High School and Luton Sixth Form College pupil, who's won more than 80 international athletics caps, has been putting Walliams through his swimming paces. 

Greg, 38, says he's often approached with "crazy ideas" to coach celebrities for high-profile charity or sporting events.  But he doesn't always take on the challenge. 

"Usually I give them a dose of reality and ask if they think they're capable of coping with the work involved.  If they're a bit of an **** I don't get involved. 

"But David's doing all right. He's extremely fit and he's not a bad little mover. 

"We've been training all over the place - Portsmouth, Newcastle, wherever he's working or appearing.  We've even swum up the Thames. 

"He's a very nice chap, the kind of guy you'd be happy to sit down and have a beer with." 

When he's not flying round the country cleaving the water with Walliams, Greg chairs the English Institute of Sport, currently spearheading a movement to change the face of sport in this country.  It has a nationwide network of world-class support services, aimed at fostering the talents of our elite athletes. 

Greg is eminently suited for the job - not only has he taken part in two Olympics, he also won a silver medal at the 1994 World Championships.  In addition, he's worked as a consultant to a number of sports teams and football clubs, including Liverpool, West Ham, Walsall and Millwall, as well as Benetton Formula One Racing and the UK's Olympic triathlon, modern pentathlon and biathlon teams. 

But he says his proudest moment was being awarded a PhD in sports science. 

And he is immensely enthusiastic about CRY (Cardiac Risk in the Young), of which he is honorary chairman.  Greg first heard about the charity when he returned from America where he studied for his MSc in human performance. 

"It was the week Daniel Yorath (the son of footballer Terry Yorath) died," he recalls. 

"His was the highest-profile case of sudden cardiac death.  CRY had only been operating about six months and their contact details were at the bottom of the piece." 

Greg got in touch and has been involved ever since.  And with his specialist knowledge of pathology and physiology, he feels the organisation is beginning to make inroads into the numbers of seemingly healthy young people who succumb to the syndrome.  The statistics are sobering - an average of eight each week, leaving a trail of heartbroken families in their wake.  Greg believes appropriate screening is the key to reducing them. 

When a young person dies suddenly and inexplicably, it is often as a result of a hereditary heart irregularity.  But unless a thorough post mortem is carried out, this can go undetected.  If it is picked up, siblings can be tested - and saved - from suffering a similar fate. 

Greg is keen for all schools to have screening facilities so youngsters at risk can be identified and treated.  And he's delighted the government responded to significant CRY lobbying by implementing an NSF chapter on arrhythmias and sudden cardiac death. 

"It was a real milestone," he says. 

"All too often these tragic events have been ignored but hopefully that's a thing of the past. 

"Doctors will no longer be able to dismiss them and put them down as natural causes.  We can put pressure on hospitals and GPs to act when this happens. 

"Many of these conditions are inherited, passed down through families.  It's important for the diagnosis and care of other siblings that screening takes place."

CRY has a highly committed team in place - legendary cricketer Ian Botham is president while former tennis ace Mark Cox is a patron.  And Greg is fulsome in his praise of chief executive Alison Cox. 

"She's the hardest working woman I know - her powers of persuasion are second to none", he says. 

Greg's home life is just as fulfilling as his professional one.  Wife Penny, a PE teacher, presented him with their first child, Maya, on Christmas Eve - "The best present ever." 

He has fond memories of his Luton schooling, is an avid Hatters supporter and intends putting something back into the community.

"It's just finding the right chance." 

He's perplexed that Luton appears to be a young cardiac-free zone and wonders if this article will stimulate floods of enquiries from anxious parents. 

CRY fact file

CRY operates in the five main areas, says Greg.

Education - increasing public awareness of the incidence of sudden death syndrome in the young as well as holding medical conferences and bereavement workshops. 

Screening across the whole spectrum - families, communities, sports/football clubs, local schools. 

Equipment donation - raising funds to give more ECG machines to local PCTs. 

Research - heavily involved in pushing it forward. 

Counselling - support for bereaved families as well as a supporters club for kids who've been diagnosed with any inherited or congenital heart condition.