FIFPro said in a statement a study of “calendar congestion and excessive workload” by 70 specialists working in professional men’s football for clubs and national teams had recommended safety standards which, it said, international football lacks.

It made 12 recommendations and highlighted several in a press release.

These included mandatory four-week off-season breaks, with two of those commitment free and mandatory mid-season breaks. It also wanted minimum four-week retraining periods after off-season breaks before players return to competition.

To manage travel fatigue management football should ensure rest periods after long-haul flights

Specific workload safeguards should be introduced for players under 21.

It also urged “seasonal match limits and fixture congestion controls”.

“Decoding the human body, performance, and sport-related injuries will be a lifelong scientific exercise for all of us,” Darren Burgess, chair of the FIFPro high-performance advisory network, said.

“However, the results of this study show that there are certain minimum standards such as adequate rest between matches, and proper off-season breaks, that are common sense, aligned with scientific evidence and, above all, required by global occupational health and safety standards.”

The Dutch-based organisation released the report three days before Sunday’s kick off of FIFA’s expanded mid-summer Club World Cup in the US.

FIFPro has led criticism of the lucrative 32-team tournament which has been crammed into an already overloaded schedule.