"Some women slip into their skinny jeans right after having a baby, but I was not one of them," the former Amazing Race contestant, tells PEOPLE.
While some women feel pressure to lose their baby weight quickly, Patterson felt this even more with her body on display everyday on television.
"Gaining weight during pregnancy – on TV! – was hard enough, but taking it off after my son was born has been even harder," she says. "I dropped a good amount of weight in the first few weeks after my son's birth in August 2015, but when I got back from maternity leave and began my new normal, things stalled out a bit."
At first, Patterson was too tired to work out, and did not want to resort to any sort of extreme dieting because she was breastfeeding and needed the extra calories.
"I knew I had to do it the hard way," she says. "That's why I created the #90DaysNoExcuses challenge – exercise for 30 minutes a day, every day for 90 days. That's it!"
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"The response has been amazing," says Patterson. "I have several co-workers and people across the country doing this challenge with me. We check in with each other several times a week to hold each other accountable."
The news anchor has already lost almost all of the 50 lbs. she put on during her pregnancy.
"I'm already back in my skinny jeans," she says. "I have a lot more energy, and I’m not even halfway done! My goal all along has been that on the final day of this challenge, which is also my birthday, I feel back to myself."
Patterson hopes her challenge inspires anyone who is struggling with their weight – especially new moms – to take on a challenge of their own.
"I am motivated to share my story because I want women to know that you don't need a 'miracle pill' or 'quick fix' to lose the baby weight," she says. "It can be done slowly, over time, in a healthy way that will set you up for good habits going forward."