‘Elite’ sport can resume behind closed doors from 2 January.
Irish Premiership games on Boxing Day and 29 December are affected by the new measures.
Boxing Day is the biggest date in the Irish Premiership calendar with a number of derby encounters, including the meeting of Glentoran and Linfield.
There is also a full programme of six Premiership fixtures on 29 December.
The initial lockdown in March also saw a total ban on sporting activity for a number months while other measures have included allowing only ‘elite’ sport to take place.
The NI Sports Forum said it recognises that the Executive had to make difficult decisions in response to the pandemic.