Personal trainer Melissa Donnelly's thriving business came to a grinding halt when COVID-19 restrictions forced her to close her business literally overnight.

Noosa fitness professional Ms Donnelly, 27, from Nirvana Life, was conducting close to 40 sessions each week, when she was given six hours' notice that the gym she was based in was closing down for good.

"My whole business died," she said.

"It was a pretty big shock to the system."

Ms Donnelly and her chef partner Raphael were left jobless and without any form of income, as neither of them were eligible for the JobKeeper assistance.

"I knew if I didn't do something right away we wouldn't have been able to rent," Ms Donnelly said.

Not disheartened, the resilient fitness entrepreneur quickly changed her focus and re-energised her meal delivery business with outstanding results.

In the space of two months, Nirvana Life Macro Meals was producing over 1000 ready-made meals each week and now employs 11 staff members.

Not bad considering the side business was originally created to service her personal training clients.

"It took off in the first week," she said.

"People couldn't go outside, so it was a blessing in disguise.

"In the space of four months sales tripled."

Now the gyms are back open, the passionate fitness trainer was able to recommence her personal business at another Noosa gym.

"I had to make the transition to Franks Gym," she said.

"It has been good and most of the clients followed."