Former “Biggest Loser” trainer Jillian Michaels may need some of her own motivational toughness to keep up with her workout regimen.

The mother of two – adopted daughter Lukensia (2-year-old) and son Phoenix (newborn), that partner Heidi Rhoades gave birth to on May 3, 2012 – is learning how motherhood is a true balancing act.

“Sometimes you’ve got to make your work and workouts co-exist,” Michaels tells the September 2012 issue of Shape.

Jillian is realizing that between running her fitness empire and being a mom, there isn’t a whole-lot-of time for herself.

“I used to tell moms that for the sake of their well-being they had to put themselves first, but I know now that’s not always possible,” says Jillian.

Here’s a little fun fact about Jillian if you don’t already know — the fitness guru actually hates exercising!

“I don’t like to exercise,” Jillian told Shape. “Let’s face it: There are plenty of other things we’d all rather be doing. I know how good I’m going to feel when I’m finished, so I make myself do it, but I like to get in and get out.

And here’s some words of advice about keeping yourself motivated to workout and stay in or get in better shape.

“While outside influences might be good catalyzers, for lasting results, you have to look inward,” says Michaels. “There is a famous quote that I live by: ‘If you have a why you can tolerate any how.’”