AN INVESTIGATION into the early impact of the COVID-19 lockdown has revealed the injury rate in German soccer spiked by more than three times the usual number.

The Bundesliga was the first European soccer competition to return and one of the first sports anywhere in the world.

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Dr Joel Mason, an Australian-raised sports scientist and researcher at the Jena Institute of Sport Science in Germany, analysed not only injuries but distance covered and sprint efforts.

Dr Mason's report, based on club and League data, found the pre-lockdown injury rate per game of 0.27 this season climbed to 0.88 in the first batch of Bundesliga matches after resumption.

Beyond that, Dortmund lost five of its starters to muscle strains in the 17-day lead-in to games, which is shorter than the three-and-a-half to four weeks AFL teams will have.

Dr Mason acknowledged the small sample size must be factored into any conclusions but that it was the "first glimpse" with data into the sports shutdown's physical impact.

He said the report was evidence the concerns and risks were "real" for all sports teams, on top of the significant increase in Achilles injuries after the 2011 NFL lockout.

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"The best teams aren't immune from load mismanagement," Dr Mason told AFL.com.au from Germany.

"I think with the AFL, though, we're at a real advantage, because sports science in the AFL is probably more advanced than the average Bundesliga club.

"A lot it comes down to the relationship between the coaching department and the performance department and how trusting the coaches are of the performance department.

"The AFL is a lot more, on average, progressive with their performance relationships with the coaching department."

Bundesliga matches remained at 90 minutes, plus added injury time, but clubs were able to make five substitutions rather than the usual three.

Almost 90 per cent of sides took advantage of this rule change.

The AFL will operate with shortened 16-minute quarters, plus time on, but an increased interchange appears unlikely.

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"Of course, in an ideal world, I would recommend they increase the interchange numbers, just to reduce the burden on the players," Dr Mason said.

"But it's a good move to reduce the quarters, and increase the rest, because the relationship between fatigue and injury is huge."

Dr Mason's research also found half the teams maintained their pre-lockdown running distances and 56 per cent matched their sprint volume, although it was less than 1km difference on average.

This was potentially because of the extra substitutions but came at a "higher cost" with injuries, he said.

The "active pacing strategy" in soccer was another likely factor, particularly once teams had a sizeable goal advantage, while the data also differed depending on the type of opposition.

Dr Mason said there was a chance AFL teams would extend the typical post-match recovery period for footballers from 48 hours to 72 in the early weeks after resumption.

"The relationship between not just that acute fatigue, where you're absolutely stuffed in the moment, but that accumulated fatigue over a season is important here," he said.

Dr Mason predicted clubs such as Melbourne and Port Adelaide, under high performance managers Darren Burgess and Ian McKeown, respectively, to be AFL leaders in this area.

He said most clubs would have run a standard fitness session at the start of this week to gain a baseline measure of where their players were at to figure out their program going forward, after not being able to track their GPS output.

Read Dr Mason's full report here.