There is a famous old photograph of Fran Cotton in action for the British Lions. He is emerging from a ferocious ruck, his face coated in mud, his hair matted with grime, the only thing visible in the murk the whites of his eyes, which gleam with manic intensity.
It's an image that summed up not only his sport but his role in it: a wholly physical battle of attrition seemingly involving very little use of the brain. It is unlikely to have occurred to anyone at the time that, 35 years after the picture was taken, Cotton would have become one of Britain's leading retail magnates.
Yet he will tell you that the rigours of rugby, the lessons he learned putting his head into places no sane man would venture unarmed, helped turn his mail order business Cotton Traders into a company that bucked high street trends to make a profit of £4.7m on a turnover close to £80m last year. Discipline, teamwork, goal-setting, not to mention bravery: crucial attributes for both an international prop forward and a businessman.
Indeed, in the year that British sport hits its zenith hosting the Olympic Games, it is no coincidence that the man behind this multi-billion pound enterprise is another ex-sportsman. Sebastian - now Lord - Coe's significant intellect and strength of personality suggest he would have made it to prominence even without the epic achievement as a world-beating middle-distance runner. But, as he reaches the final lap in his tenure as chairman of the London Organising Committee of the Olympic Games, he believes that the skills he learned tearing round the tracks of the world, breaking records and winning medals, gave him a unique grounding for a career in business and politics. It's true that without Coe, London would not be gearing up for the party to end all parties this August.
Talking to those who swapped spikes and studs for collar and tie, the playing field for the boardroom, we should not be surprised by the numbers who have made the crossover. From Dave Whelan and JJB, through Sir Jackie Stewart's engineering company to Sir Tony O'Reilly's media empire, these are people driven by a potent mix of determination to succeed and ability to confront failure. That is the thing about sport: its rhythms are stark. You win or you lose. There is no compromise, no fudge, no grey area. Being schooled in that knowledge is immensely helpful in a business career.
And yet nobody made a fortune by merely transferring their sporting self into a new playground. For every Cotton or O'Reilly, many others fall by the wayside or resort to the speaking circuit, paid to endlessly relive past glories.
Indeed, all the sporty businessmen we feature here will tell you this: if they had known then what business has since taught them, how much more successful they would have been as sportsmen.
The former hurdler and Olympic silver medallist is now chairman of Fast Track, the sports events agency.
There is a huge carry-over from sport to business. In terms of determination, focus, ability to channel, there is so much you learn on the track that can be applied in your work. And although I came from an individual sport, I was merely the most visible member of a team. I learned pretty quickly that without the coaches, physios etc I didn't stand a chance; their work put me in a position to compete properly. So I was always fully aware of the value of teamwork and the essential requirement to delegate and trust - which are also crucial to business success.
But I think the most significant motivator you will find in most sportsmen who have a business career in later life is this: a fear of failure.
That is what drove me as a competitor, and that's what drives me as a businessman. I suppose you could say that this is at the heart of the competitive streak you need in both. It is not simply a matter of winning. It is to do with self-esteem, feeling that you are doing the best you can. The engine in both sport and business, I guess, is the need to feel successful. And an absolute horror of the opposite. I was an asthmatic kid from a council estate, so the opportunity to rise above everyone else - those who I felt were more advantaged - was always a huge motivator for me.
I competed at a time when athletics was amateur. Shamateur, you might say, but there was so little money in it when I retired from competition that I had to find a way to earn a living. There was no plump pension pot there for athletes of my generation. I did a variety of things, teaching, media work and so on. But I was keen to remain within the sport if I could.
I started a promotions agency in 1984, which grew to be the fourth-biggest in the world. I sold it in 1997, at almost exactly the time the British Athletics Board went into administration. The administrators asked me if we would take over the events and contracts side of the sport, which we did, creating Fast Track. Since then, we have raised over £100m for British athletics through television contracts and sponsorship. Now we have been absorbed into the Chime Sports Marketing Group and have more than 450 people working for us around the world.
And the thing is, I still start every day in business as I did when I was an active sportsman: hoping I can do better than I did yesterday.
The marathon runner is one of the best-paid athletes in the world, earning at least £250,000 every time he competes. His business ventures in his native Ethiopia range from hotels to importing cars and exporting coffee.
I don't see it as a duty to spend my money in my country - it is what I want to do. There is nowhere else I would like to invest.
Yes, I could have moved to somewhere like Monte Carlo, where lots of sports people live, enjoying a life without tax. But for me, the point of money is to use it, not to sit on it. Besides, I wanted my children to grow up in my country, I wanted them to be as proud of Ethiopia as I am. It is an amazing place. The GDP here is $200 a head. It is a miracle how my people live on $200 a year. When I look at how they live, I think how amazing they are. Do you think Americans could live on $200 a year? Impossible. But they do here. The Ethiopian people are incredible. And I want my businesses to help them improve their lives. Why not?
I have run my whole life on the clock. Now in business, it is the same. I have to do things not tomorrow, not today, but yesterday. I have just built a tower block here in Addis. People told me it would take two years to build. I said no, it has to be finished in seven months. I was told that was impossible, but I was there on the site at six every morning before I went training to make sure the work was on schedule, telling everyone there to hurry. And it was done.
You need three things to win a race: discipline, hard work and, before everything maybe, commitment. No one will make it without those three. Sport teaches you that. It is not enough just to win the race, it is how you handle the lessons, how you improve. After they win something, some athletes don't make the most of it, because they are not disciplined. And it is the same in business.
Running makes me a better businessman. It's the discipline. Actually, I couldn't run my business without running. If I have a problem with it, I don't sleep on it, I go for a run. And by the time I have finished running, I have thought of a solution.
There is no secret to my success. I just know what I am trying to do. I want to give work to people who want a job. And at the moment, I employ 650 people. So it is good.
The winner of an Olympic gold medal in the 100m breaststroke at Seoul in 1984, he is now MD of the business consultants Lane 4 Management Group.
The first thing I had to learn when moving from sport to business was to stop being so selfish. My entire sporting career had been centred on sucking out the expertise of others entirely for my own benefit. In business, you don't get very far if it is all about your ego. You can't be a user in business; leadership is about humility and the spirit of enablement. The person who taught me most about business was my coach. Coaching is very akin to running a company, in that your whole effort is to get the best out of other people.
When I came into business, I drew heavily on my experience as a sportsman. What I can't say is whether that is because it was particularly relevant or because it was all I knew. If I had gone into business straight from university, where I had run the debating society or played in the orchestra, I would have drawn useful experience from those activities.
And I learned pretty quickly that the timescales are very different. The action/reaction in sport is almost instantaneous: if I do this, I get that. In business, if I do this, it may well take some time for the consequences to reveal themselves. So you need an altogether higher degree of patience.
That said, you can draw very useful lessons from sport. Goal-setting is an obvious one. Plus, to be a top sportsman you have to be good at a lot of things beyond your discipline to succeed. You need real expertise in diet, physiology, psychology. A study of top sportsmen suggested they were motivated by two things: a need to win, plus a desire for mastery. Mastering your discipline is a huge motivation for businessmen too.
Above all, though, the most useful business lesson I learned in sport was the ability to handle pressure. As an Olympic performer, a whole four years of preparation came down to one minute on one day. You had to retain your composure at that moment to allow yourself to deliver. That skill has really stood me in good stead, building a company that employs more than 100 people.