Riley Rees-Turner is an accidental elite rower.

The 23-year-old was a promising Australian rules player in his teens, playing for South Fremantle in the Western Australian Football League colts competition, before injury ended his dream.

"I was having some issues with concussions and things like that," Rees-Turner said.

"I was in the process of giving it [football] away, and I was still coming to terms with what it meant in terms of getting back into the everyday life."

"It did sting."

School visit changes everything

Rees-Turner was acclimatising to being a regular teen, when the Western Australian Institute of Sport (WAIS) visited his school.

"It kind of came out of the blue. We knew the testing was coming to school, but I was in a bit of a limbo at that point," he said.

"I was like 'I just want to play basketball with my mates in PE' and I don't want to push my body to the limit.

"And then Jamie the [WAIS] head coach came over and said they wanted to try this bunch of boys."

Rees-Turner was put through a battery of tests, including being put on an assault bike and having his strength tested.

He was selected as a potential cyclist and rower, and chose the latter.

"Went down to the sheds, loved it and then nine months later was on the Australian junior team," he said.

Growing pains

It wasn't without some growing pains, as he went from being a land-dweller to a water athlete.

"So just out in the sculls getting used to what a rowing boat was, how tippy it is, how easy it is to flip, putting oars in the wrong way.

"Having to swim to shore to get back in [after falling out].

"There was a challenge of being not great at something, and then working your way up to being competitive on the world stage."

Rees-Turner now trains full-time at WAIS, with an eye to making the Olympic team for the LA Games in 2028.

But for him and other rowers targeting the next Olympics, there will be changes they need to contend with.

In LA, the rowing course will be 500 metres shorter than any other competition, reduced from 2,000 metres to 1,500 metres.

That's because rowing will be held at the Marine Stadium in Long Beach instead of the Lake Perris State Recreation Area in Riverside County.

The move means organisers won't need to build a satellite village for athletes, and keeps the Games in a smaller area. The trade off is the reduced course, which was originally used in 1932.

Studying the shorter course

"Rowing has been raced over 2,000 metres for a very long time. It's been the standard racing distance since 1912 for males, and in 1988 for females," said Dan Astridge, who is completing a PhD at UWA, embedded at WAIS to study the change in distance.

Since 1912, only one Games has held a race shorter than 2,000 metres, and that was London in 1948, the first Games after World War Two.

"We are doing research around how can we optimise preparation and performance over this new distance," Astridge said.

The challenge for rowing programs around the world stems from the standardisation of the 2,000-metre course, which dictates performance tests on the ergometer (rowing machine) as well as race strategy.

"My first thoughts were around, how do training and sessions and preparations change? Do we have to identify new athletes at all, when we're looking at early talent identification and bringing these athletes up?"

As things stand, rowing across the four years to LA will continue to race at 2,000 metres, including when competing in qualification events.

Astridge said consideration might be given to changing the athletes who qualify, if they were more suited to the shorter distance.

Early evidence

Astridge has begun conducting studies to assess the differences in performance across the two distances, starting with which energy system would be in use, the aerobic or anaerobic.

The aerobic energy system refers to the combustion of carbohydrates and fats in the presence of oxygen, while the anaerobic system is when glucose is broken down without oxygen.

More simply, a person can work longer in the aerobic state, but faster and harder in the anaerobic state.

Using gas collection, Astridge determined that the anaerobic contribution for the 1,500 metre race was only 5 per cent higher than the 2,000 metre race.

"We hypothesised it would be about 15 per cent difference just based off previous literature in other sports," he said.

"So we weren't sure if that was a pacing limitation or if that was [because] we used junior athletes."

He said rowers might have also been settling into their normal racing rhythm rather than the ideal 1,500-metre race pattern.

"Athletes are so familiar with racing over 2,000 and what the race rhythm should feel like over 2,000, a 1,500 is completely different.

"Pacing patterns might have to change, which will have to be trained, they won't be able to kick that habit really easily."

The good news for rowers like Rees-Turner is they have four years to prepare as they seek a spot at the LA Games.

But for now, he has to watch Australia's rowers compete in Paris.

"I'm so envious of them," he said.

"I've got guys that I've raced against and I've looked up to for years now that are going again."