The "Cool For The Summer" hitmaker says she finds the process "therapeutic", reported Us weekly.
"It's definitely therapeutic. I feel the most confident when I'm in the gym. Whenever I'm training, whether it's boxing, kickboxing, Muay Thai, jiu-jitsu," Lovato says.
The 24-year-old singer says she hopes that by sharing her own gym routines, she can inspire other women to get healthy and feel comfortable in their own skin.
"I stay confident in my own life by daily affirmations -- looking in the mirror, telling myself I'm beautiful no matter what and just learning to accept my flaws for what they are and knowing that, you know, my curves are beautiful, and I am who I am," she says.