City Gym won't be offering any personal training under level 2 as a precaution.
"We are taking our precautions like everyone should be doing and everything is running smooth."
Clients must bring a towel and adhere to the 2m social distancing at all times, as well as signing in on arrival and signing out when leaving the facility.
"I'm impressed with everybody. They are all using the sanitisers and everything which is good."
Owner of Revitalise, Audrey McCosh, said they were steady throughout opening day.
"We had a really good day, had a really fun day. People were really glad to get back.
"It's great, it sounds a bit silly, but this is my happy place. And having people back, the music blaring, it just makes you smile to see people."
McCosh said they have shifted their cardio gear and have marked the floor to make sure 2m distancing is in place.
McCosh noted there were two ends of the spectrum for her clients.
"We had a little bit of a mixed reaction.
"People were dying to get back in there. I might contradict myself here, but I think some people are still a bit worried about going out."
McCosh, who mainly works on nutrition plans, has been working online under level 3 and has seen 30 clients over the first two days of opening.
Revitalise staff have been in constant contact with their clients during levels 3 and 4 to make sure they are okay and meeting their goals.
"We've rung every client every week to make sure they been okay during this time and just touching base."
McCosh said the lockdown has made some realise how much working out is part of their life.
"The majority of my clients are middle aged women and they aren't gym junkies, but they have been messaging non-stop saying 'I can't wait to get back in the gym'.
"I think they really appreciate how important this is and has become part of their life, which I think is fantastic. It makes me smile."