The women-only class - U B Yr Own Gym - will be held in two weeks.
Mr Millar said while working on physical needs the Salvation Army "unapologetically" will also be developing the muscular faith of participants.
"Also part of it is addressing the mental issues, thinking about self control.
"We address the whole person, it's very much a holistic thing. People can get depressed because they have things they're struggling with. When you do exercise, the endorphin hormone kicks in and you feel better about yourself."
Mr Millar, who is in his 70s, said he does the exercises every day and they have helped him develop and maintain his strength and balance.
A DVD is on offer for people to exercise at home.
The free U B Yr Own Gym class for women will be held at the Salvation Army Church at 271 Old Taupo Rd, on Sunday, June 9 at 2.30pm.