In the wake of the Club World Cup, which ran through June and July in the US this year, FIFPro's director of policy and strategic relations Alexander Bielefeld called the tournament "a wake-up call in the context of a warming planet".

With many of the matches in the club tournament taking place in the middle of the afternoon in the US when temperatures often soar well past 30C, FIFPro flagged the "severe challenges to players' and participants' safety and health" when playing in extreme conditions.

To combat this, it said "the existing schedule (for the World Cup) and venue selections may need to be reassessed to better safeguard player health, protect fan well-being, and support optimal performance".

The union also called for longer half-time breaks and more regular cooling breaks.

FIFPro general secretary Alex Phillips said "we are having informal discussions (with organisers) about the use of air-conditioned stadiums", but added "nothing concrete" had arisen from talks.

The report also highlighted the impact of the Club World Cup on players' workloads following the club season.

Bielefeld said the "timing of the Club World Cup had a very negative impact" on players' rest periods and their pre-season.

According to the report no players from the analysed participant clubs reached the minimum 28-day off-season and many started the current season without the minimum required four-week pre-season and re-training period.

Nottingham Forest and New Zealand striker Chris Wood told journalists on a call presenting the report: "For us as players it's vitally important that we have the recovery period to go again."

The 33-year-old added not having the minimum recovery period was "feasible over one or two seasons, but not for five or six".

The union also flagged the increasing number of minutes being played by star youngsters such as Barcelona's Lamine Yamal.

Yamal racked up over 8,000 minutes of playing time for his club and country prior to turning 18, which FIFPro said far surpassed that of previous "generational talents" like Andres Iniesta or Kylian Mbappe.

Chair of FIFPro's high-performance advisory network Darren Burgess said "players are still growing and maturing until 24-25 years of age, overexposure before then is taking an injury risk".

Wood added a balance needed to be struck in finding the right amount of time for teenagers to be playing.

"When you're young, you just want to play football. You don't think about how your body is changing and growing," he said.

"It's about finding that balance by educating younger players about the risks."