Premier League players and club staff will need to take a lateral flow test every day in order to get into training grounds as part of new measures agreed on Tuesday.
The action is aimed at stemming the rising number of positive cases.
The Premier League confirmed on Monday there had been 42 positives over the previous seven days.
It is the highest figure recorded since Covid testing began as part of Project Restart during the 2019-20 season.
Outbreaks at Tottenham and Manchester United have caused the postponement of two league games within the space of three days.