‘What time is it, please?” asks Jack McCaffrey. He’s just given us a generous chunk of his time and, with that, politely excuses himself. No one could function at the top end of a so-called amateur sport without being a master of time management.

A lot of people still think GAA players are some sort of slaves to their amateur status, struggling with the time commitment, wondering if they should be playing something else. But they’re wrong. Because for all the research and advancement in that broad spectrum known as sports science, one thing remains certain: we don’t choose our sport, our sport chooses us.

McCaffrey may be a perfect illustration of this. It’s Wednesday morning in Croke Park, and he’s on hand to promote the GAA-GPA’s partnership with the Childhood Cancer Foundation. Later, he tells us, he’s got another charity event to organise at University College Dublin, which means it will be Thursday before he joins up with the Ireland team that plays Australia in Croke Park tonight.

Why McCaffrey is even playing International Rules after the season he’s just had is another measure of his commitment. It helps that he clearly loves what he’s doing: if winning a second All-Ireland football title with Dublin didn’t bring enough reward for that time he’s putting in, winning the Footballer of the Year award plus an All Star definitely did. Not many 22-year-olds can be walking around Dublin right now with a greater sense of contentment.

Yet there is also the sense that McCaffrey would be enjoying his football even if there were no rewards. He actually describes it as a healthy hobby, “something else that keeps you sane”, while he goes about the rest of his daily business, which right now is his fourth-year medical studies at UCD. He’s got exams coming up too, by the way, and next summer, when Dublin go about defending their All-Ireland title, he’ll be starting his hospital training. He wouldn’t have it any other way.

Bouncing ideas

One of his classmates at UCD happens to be the 800-metre runner Mark English, and McCaffrey admits they often bounce ideas off each other.

English is also operating on somewhat amateur ideals, given that he’s studying full-time while also considering himself a full-time athlete. He will be taking next semester out in order to concentrate solely on the Rio Olympics, having secured the qualifying standard this summer. Again, for now, English wouldn’t have things any other way.

McCaffrey also admits he dabbled in athletics as a youngster, hardly surprising given his “frightening pace”, as RTÉ’s Darragh Maloney described it. McCaffrey’s father, Noel, also an All Star defender with Dublin, back in 1988, had an equally swift turn of pace in his prime, and long after retiring could be spotted belting out the laps around UCD. Those McCaffrey genes would have been just as comfortable on the track as the football field.

Indeed McCaffrey might well have chosen rugby, too. Back in 2009, he was the dashing winger on the Belvedere Junior Cup team that nearly upset Terenure in their first-round clash at Donnybrook. Terenure won 17-13 (and went on to lift the cup), although anyone who witnessed that game will recall it for McCaffrey’s solo try from outside his own half.

Asked to choose

Not long after that, he was effectively asked to choose between rugby and Gaelic football. He chose the latter, mainly because it had already chosen him.

“It would be very difficult for me to picture not having it,” he says. “All my friends were playing Gaelic, with Clontarf, and that’s probably what drove me on originally.”

English’s sporting pursuit, meanwhile, went in the opposite direction, given that he dabbled in Gaelic football as a youngster.

As well as playing with his school, St Eunan’s, English also spent a few seasons with Letterkenny Gaels (to the mild dismay of his father, Joe, who had helped coach rival club St Eunan’s to a Donegal county title). English certainly enjoyed it – especially the team camaraderie – and if his running talents hadn’t been spotted when winning the egg-and-spoon race at the local sports day, things might well have been different.

Yet not once does English look across the lecture hall at UCD and wonder should he be in McCaffrey’s shoes. The sport of athletics chose him, and he wouldn’t have it any other way.

There was another perfect reminder of all this, earlier on Wednesday morning, as the world began to pay tribute to Jonah Lomu. Long before becoming rugby’s first truly global superstar, the greatest player of his generation, Lomu was displaying his astonishing athletic talent. One of the most poignant testimonials to this talent was the picture of the athletics honours board at Wesley College in South Auckland, where, in the 1989 junior sports events, Lomu won the 100 metres, 100 metres hurdles, 200 metres, 400 metres, discus, shot, javelin, long jump, high jump and triple jump.

The only events Lomu didn’t win were the 800 metres and 1,500 metres, and there can be no doubt that had he chosen athletics, with obvious potential in the decathlon or any of those field events, Lomu would also have risen to the top.

Instead, at 19, he became the youngest All Blacks Test player in the two-Test series against France. For several years after that, he retained the look of a starry-eyed schoolboy who couldn’t quite believe he’d become a rugby superstar.

Only now, especially given the state that global athletics finds itself in, comes the complete realisation that Lomu didn’t choose his sport, his sport chose him.