Thirty degree training sessions, insights from NZ champs and a late night drug test - all part of the build up for Joseph Parker

In an hour long private session held in a room with the heat pumped up to 30 degrees, Joseph Parker looked impressive in front of a handful of family and friends.

Parker, 26, showed no signs of worry when training in his hotel in front of loved ones. Source: 1 NEWS

But trainer Kevin Barry admitted yesterday he thought his man was a little off.

Today, not quite as sharp, Barry said.

"He's going through the moves, still good work but definitely not as good as he was last night."

That might have something to do with WADA drug testers turning up late the night before to take a sample from the Kiwi - Anthony Joshua has been tested as well.

"We'd just finished training, Joe had shower, [the testers arrived] after the shower.

"He was [dehydrated]. They had to wait a couple of hours for him to finish his dinner and load back up with water again!"

Yesterday's behind closed doors session was all about working up a sweat for Parker, staying loose, but also running through that crucial game plan once again with Barry.

Several boxing luminaires and former New Zealand title holders were also on hand also to observe the private session.

"Joe's hand speed has sort of trebled since he's had the elbow operation, his fitness and his attitude’s just amazes me", six time NZ champion Barry Galbraith said.

Parker said the amount of support he has received building up to this Sunday is moving.

"When you have support like this you're not only fighting for yourself, you're fighting for everyone that's here."

Parker will have another light session today before the weigh in on Saturday NZT.