Story highlights Stevens is relishing life in the saddle having returned to being a jockey past his 50th birthday

Injury forced his original retirement and he'd been enjoying an acting career

But the lure of horse racing proved too much and he has returned in some style

He argues his role as a broadcaster has enabled him to become a better jockey

Every morning before riding, Gary Stevens has to walk four miles.

The walk is a necessity, the only way the 51-year-old can get his ailing knees slowly warmed up and working, capable of dealing with the demands on those damaged joints of riding some of the world's best horses at speeds of up to 45 mph.

When the American first retired in 2005, he had enough money in the bank from a glittering riding career to kill any thought of a comeback. Then there was the ensuing broadcasting career, not to mention acting forays in the movie " Seabiscuit " and the television series "Luck."

But he finds himself back in the saddle. "This is middle-aged crazy," he says -- and without cracking a smile, all too aware of the risks being taken.

One only has to watch the clip of him being trampled like a rag doll in the 2003 Arlington Million race, suffering a punctured lung and a fractured vertebra in his back, to see that.

"People retire and play golf or go fishing. This is my fishing. I never thought I'd say so at this time of my life but I'd rather be on the race track than on the golf course, and I like golf," says Stevens, who started racing again at the start of last year.

"And the 50s are the new 30s right? Anyway, I'm not the only old guy out there. Look, you've got Fred Couples in golf and he's doing alright."

But his return demanded sacrifices. Stevens had to shed the equivalent of 10 bags of sugar off his body and get down to a racing weight of 114 lbs (51.7 kg) in a grueling two-month training regime.

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In addition, his knees are damaged to the point he knows he will need surgery to replace them.

"You don't realize how good it is until it's gone," he told CNN, explaining his decision to retire.

"Being retired allowed me to look back and actually enjoy some of the great things that had been accomplished in my first career. I was like 'wow.' If you won a big race, you could never rest on your laurels as there was the next day, the next race.

"Then there were the injuries and always thinking and obsessing, 'When will I get back?' I realized how good it was and I asked myself, 'Can I do it again?'

"I didn't want to come back and tarnish what I'd done in the past. I wanted to come back at a high level."

Sporting comebacks don't generally tend to end well. Stevens, though, has provided a Hollywood epilogue befitting his secondary career on the silver screen.

Last year, he won 69 races including the prestigious Preakness Stakes and the Breeders' Cup Classic , and he is fast approaching 5,000 career victories on American soil alone. He notched up $100 million in winnings by the age of 30, and he is now nearer the $225 million mark.

There are parallels between Stevens and another giant of flat racing, Lester Piggott, who famously returned to the saddle aged 55 -- in his case after a year in prison for tax evasion. Much like Stevens, his success was almost immediate, the British rider capping his return by winning the Breeders' Cup Mile within 10 days of his return.

"It's funny," says Stevens, "but no-one's actually asked me about the Lester link before. The way he rode that Breeders' Cup, arguably one of the best rides of his career, making all the right moves at the right time. So my thought was, 'If he can do it and I'm younger, then why not.' The guy was a bit of an inspiration."

Luck has also played a part in Stevens' return to the saddle. He had previously been enjoying an acting career in the Michael Mann-directed TV series "Luck" alongside the likes of Dustin Hoffman and Nick Nolte, but it was cut short before the second season began due to concerns over animal safety.

"If that hadn't been axed, I'm not sure I'd be doing this," he says. "I was all set to meet in makeup the next day at 4.30 a.m. when I got an email saying it might be scrapped.

Photos: Triple Crown winners Photos: Triple Crown winners Kentucky Derby and Preakness Stakes winner American Pharoah wins the 147th running of the Belmont Stakes in New York on Saturday, June 6, to become the first horse to win the Triple Crown since Affirmed did so in 1978. Hide Caption 1 of 12 Photos: Triple Crown winners Sir Barton was the first horse to earn the Triple Crown of Thoroughbred Racing, as it would come to be known, by winning the Kentucky Derby, Preakness Stakes and Belmont Stakes in 1919. Hide Caption 2 of 12 Photos: Triple Crown winners More than a decade later, Gallant Fox captured the Triple Crown in 1930. Hide Caption 3 of 12 Photos: Triple Crown winners Jockey Pat Beasley rides Omaha in 1936. The horse won the Triple Crown in 1935. Hide Caption 4 of 12 Photos: Triple Crown winners War Admiral won the Triple Crown in 1937. He won 21 of his 26 career starts. Hide Caption 5 of 12 Photos: Triple Crown winners Whirlaway, right, won the Triple Crown in 1941. Hide Caption 6 of 12 Photos: Triple Crown winners Count Fleet, who won the Triple Crown in 1943, is adorned with flowers after winning the Preakness that year. Hide Caption 7 of 12 Photos: Triple Crown winners Assault won the Triple Crown in 1946. Hide Caption 8 of 12 Photos: Triple Crown winners Citation won the Triple Crown in 1948. Hide Caption 9 of 12 Photos: Triple Crown winners Secretariat, left, heads to victory at the Kentucky Derby in 1973. Considered by many to be the greatest racehorse of all time, Secretariat still holds the record for the fastest times in all three Triple Crown races. He won the Belmont by an astounding 31 lengths. Hide Caption 10 of 12 Photos: Triple Crown winners Jockey Jean Cruguet guides Seattle Slew to the Triple Crown in 1977. Hide Caption 11 of 12 Photos: Triple Crown winners Jockey Steve Cauthen rides Affirmed to a Belmont victory in 1978. Hide Caption 12 of 12

Photos: 'The fastest two minutes in sport' Photos: 'The fastest two minutes in sport' 'The fastest two minutes in sport' – Introducing racing's "rock star." Hide Caption 1 of 14 Photos: 'The fastest two minutes in sport' 'The fastest two minutes in sport' – California Chrome has arrived at Louisville for the Kentucky Derby build-up and remains the favorite to win the famous trophy. Hide Caption 2 of 14 Photos: 'The fastest two minutes in sport' 'The fastest two minutes in sport' – A crowd of 150,000 is expected to flock to Churchill Downs to see the field leave the stalls for the 140th Kentucky Derby. Hide Caption 3 of 14 Photos: 'The fastest two minutes in sport' 'The fastest two minutes in sport' – Last year's winner of a race billed as "the fastest two minutes in sport" was Orb, ridden through the mud to victory by jockey Joel Rosario. Hide Caption 4 of 14 Photos: 'The fastest two minutes in sport' 'The fastest two minutes in sport' – This year's favorite when they enter the first turn is California Chrome, a horse that cost its owners a mere $10,000 to breed. Hide Caption 5 of 14 Photos: 'The fastest two minutes in sport' 'The fastest two minutes in sport' – California Chrome, pictured with mother Love the Chase as a foal, was a huge bargain -- the mare costing $8,000 and breeding with sire Lucky Pulpit for just $2,000. Hide Caption 6 of 14 Photos: 'The fastest two minutes in sport' 'The fastest two minutes in sport' – The colt has become a surprise hit in thoroughbred racing, upstaging far more costly rivals in something of a fairy tale. Hide Caption 7 of 14 Photos: 'The fastest two minutes in sport' 'The fastest two minutes in sport' – All eyes in the U.S. will be on Kentucky from dusk until dawn as the world's best horses battle it out for the $2 million purse. Hide Caption 8 of 14 Photos: 'The fastest two minutes in sport' 'The fastest two minutes in sport' – Star jockey Gary Stevens returned to the sport before last year's Kentucky Derby and is targeting a fourth win in the prestigious race on Candy Boy. Hide Caption 9 of 14 Photos: 'The fastest two minutes in sport' 'The fastest two minutes in sport' – The stands will once again be full to the brim for the key occasion of American thoroughbred racing. Hide Caption 10 of 14 Photos: 'The fastest two minutes in sport' 'The fastest two minutes in sport' – Flamboyant hats are never far away on major race days. Hide Caption 11 of 14 Photos: 'The fastest two minutes in sport' 'The fastest two minutes in sport' – Spectators come in all shapes and sizes each, including a quartet of AXE astronauts in attendance at the event a year ago. Hide Caption 12 of 14 Photos: 'The fastest two minutes in sport' 'The fastest two minutes in sport' – Colorful head pieces are always a feature on race day and, in the case of this punter, hopefully lucky horseshoe sunglasses. Hide Caption 13 of 14 Photos: 'The fastest two minutes in sport' 'The fastest two minutes in sport' – Last year the rain came down but those gathered for the event remained undeterred by the mud underfoot. Who will the sun shine down on in 2014? Hide Caption 14 of 14

Photos: Star jockey turns photographer Photos: Star jockey turns photographer The jockey turned photographer – Many of former jockey Richard Dunwoody's pictures have an equine theme, including this of a boy and his blind pony in the countryside near Chimaltenango in Guatemala. Hide Caption 1 of 10 Photos: Star jockey turns photographer The jockey turned photographer – These images were part of a project by animal charity The Brooke -- here working mules and their drivers depart from a brick kiln close to Aligarh, an Indian city near Delhi. Hide Caption 2 of 10 Photos: Star jockey turns photographer The jockey turned photographer – A man drives his horse at full tilt down a dual carriageway with a large load of empty water barrels in Faisalabad, Pakistan. Hide Caption 3 of 10 Photos: Star jockey turns photographer The jockey turned photographer – A carriage driver washes his mule's head in the Nile from a riverboat in Egypt. Tourism is not quite so buoyant in Luxor and drivers are finding it extremely hard to make a living. Hide Caption 4 of 10 Photos: Star jockey turns photographer The jockey turned photographer – Working donkeys at a brick kiln in Gujranwala in Pakistan. The owners take great pride in them, often adorning their bridles with tassels and cloths. Hide Caption 5 of 10 Photos: Star jockey turns photographer The jockey turned photographer – A dehydrated working horse about to be treated at a Brooke clinic in Lahore, Pakistan. Hide Caption 6 of 10 Photos: Star jockey turns photographer The jockey turned photographer – A tired working donkey carrying construction materials in a slum in Delhi, India. Hide Caption 7 of 10 Photos: Star jockey turns photographer The jockey turned photographer – Photography is a complete career change for Dunwoody, who (pictured right) rode Miinnehoma to victory in Britain's prestigious Grand National jumps race in 1994. Hide Caption 8 of 10 Photos: Star jockey turns photographer The jockey turned photographer – Arguably his most famous ride was Desert Orchid, who won the prestigious King George VI Chase in 1989 and 1990. Hide Caption 9 of 10 Photos: Star jockey turns photographer The jockey turned photographer – But Dunwoody insists he doesn't miss the rigors of horse racing and the ensuing falls, such as this one on Spring Hay. Hide Caption 10 of 10

"Via a couple of phone calls a few minutes later, sure enough, it was over. I was just lost, it was like losing a family member. In that first week, I made the decision to come back."

Stevens will forever be grateful for his acting career -- he describes it as one of "two dream jobs I've had" -- but it has also acted as Cupid for him, having met his wife Angie on the first day of filming "Seabiscuit."

"I turned up on the set and this lady appeared as a silhouette. She said, 'You look lost,' and I was like, 'I need to find where I'm supposed to be.' I explained I was playing George Woolf and she showed me to my trailer."

He did not lay eyes on her for the next five months but, as the movie wrapped up, they met again, went for dinner and the rest is history.

Such Hollywood-esque nuggets are littered throughout the life of the man from Caldwell, Idaho.

There was the hip condition called Perthes syndrome that forced him to wear a metal brace for 19 months at the age of seven, his decision to drop out of high school in 1979 to become a jockey -- also the year he won his first race -- difficulties with alcohol in his career, and now the ongoing return to the sport of kings: all quite remarkable for a grandfather.

But he argues he is currently at his happiest. "It's an unbelievable ride, better than the first time around," he says.

"It's been very gratifying as I don't think people expected me to come back at the level I did. I didn't expect it. But I'm very hard on myself and motivated so I made it happen. That was the thing missing in my life, I just didn't have anything to push myself."

How is the Stevens Mark II in his own mindset as a jockey?

"I think I'm better in the sense that my broadcast work has made me more analytical," he adds. "I really think watching racing for seven years has developed my skills.

"It's been crazy, what a journey, hey? If it ends tomorrow I'd be a happy guy. My life is more than half over and it's been a good life."

The Hollywood ending, it would seem, has already been sealed.