Gym-related injuries are costing millions, and accidents relating to the popular fitness training regime F45 are the latest addition to the ACC bill.
Gym or fitness-related claims paid out by ACC for 63,614 injuries in the year ending June 2018 totalled $42,619,086. This included injuries relating to CrossFit training and F45.
Over the past five years, a whopping $171,769,879 has been forked out in relation to gym, CrossFit and F45 injuries.
Of these, 51 claims related to F45 injuries, which cost a total $30,288.
Forty-six of these injuries occurred in the year ending June 2018 - mirroring the rapid growth of the exercise since it launched here in 2017.
F45 training is a type of high-intensity interval training described as "functional training" over 45-minute classes.
More than a dozen studios have popped up around New Zealand since it arrived here from Australia.
Enthusiast Sarah Tanner took up the regime two months ago. She's two weeks into the latest "eight week challenge" at the One Tree Hill F45 studio.
"I'm absolutely addicted, I love it so much," she said.
The 40-year-old switched from her old gym regime as she was after something a bit different, seeking the motivation that typically came with group exercise.
"With the gym you're sort of left to your own devices, unless you have that personal trainer aspect," she said.
Tanner hadn't suffered any injuries as a result of the exercise classes. She said "common sense prevailed" when it came to starting new exercise regimes and it was important to know your limits and start slowly.
When it came to gym and fitness-related injuries, Tanner suggested people were more likely to injure themselves following their own regime.
"There are so many fitness apps these days, and if you're doing it at home a lot of people don't know what the heck they're doing," she said.
"There's no one to assist them if something goes wrong."
Class sizes at the studio depended on the time of day, but Tanner said they were generally pretty small.
Each session was made up of about 12 people, and there were about three trainers on the floor for each class.
ACC senior injury prevention specialist Gareth Smith said most F45-related injuries involved the lower back, knees and shoulders.
A rise in participation levels was reflected in the increase in the volume of ACC claims for gym and fitness injuries year on year. F45 claims were currently small, Smith said, and came at a relative cost.
"It's important to take some time to learn how to do the exercises well and recover well if you're injured," Smith said.
Smith said many of the injuries were avoidable.