PNE went into the current international break in second place, winning three games on the bounce in the run-up.
They briefly went top of the table after beating Charlton on November 3.
This is a third season in a North End shirt for Fisher, who was the first signing made after Alex Neil’s arrival as boss in July 2017.
In that time the right-back definitely thinks the quality and intensity levels have gone up in the division.
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Fisher told the Lancashire Post: “I’d say that since I’ve been here the Championship has got tougher.
“You look at some of the players who have played in this league. In my first season here we were up against Ruben Neves at Wolves who had played in the Champions League.
“At Charlton the other week, Berman Kayal was in their team.
“I was with him at Celtic and he played Champions League football there.
“Last season Reece James was on loan at Wigan and now he is in Chelsea’s team.
“There are some really good players throughout the league and it is great to have that test.
“We have quality players in our team, let’s not forget that.
“For us to have done what we have so far this season is testament to how hard we work and the quality here.”
The international break, which is the last one until the end of March, offers the chance for the squad to get some much-needed rest.
But there were a couple of intense days of training this week and things return to schedule next week in the build-up to playing Derby.
Said Fisher: “A bit of rest is always welcome, especially with how hard we train here.
“Even in the international breaks we train hard on the days that we are in.
“The intensity we train at is high, there is a big demand on you from the manager.
“I think the demand here at Preston is more intense than I’ve experienced before.
“The demand at Celtic was there because of how big the club is but that wasn’t really driven by anyone – it was just the size of the place.
“Here, the manager drives the standards and the demand is there from him.
“If you are with him, you have got his backing 100%.
“He is the type of manager I like, I get on with him really well and like the training and approach we have.
“This is the last break we will have for quite a while – the next one is in March.
“Some of the lads will use the time to zone out, I’ll have a rest but I do like to tick over and do a bit of work.”