The mother-of-two took to Instagram to share a photo of herself before she began her body transformation and now with the two photos barely looking like the same person.
Tammy told her followers she changed her appearance by eating "beautiful healthy food in abundance" and training "consistently and effectively".
"In these photos, on the left I was working out a little, I was restricting my calories HUGELY, lots of cardio, I wasn't being healthy, I didn't really know what I was doing," she told her followers.
"To the right which was today, I train consistently and effectively, I do mostly weights. I eat SOOO MUCH beautiful healthy food in abundance (while still having treats/indulging when I want).
"Not to mention I had my two beautiful kids in between these as well! This has taken YEARS of consistent hard work and it has been a hell of a journey but I have loved every step."
She added, "The place I am in now not just physically but mentally is just incredible. I went from being lost to being completely in love with life!! YOU CAN TOO!! It is never too late to start. You can completely transform your life, believe that!"
Tammy also told her followers they could start their own transformation by using her TammyFit app, where an 8-week challenge will be kicking off tomorrow.
Her followers were blown away by the before and after photos with one user writing, "Love that you did this naturally with hard work while being a beautiful role model for your babies."
"Hard work, discipline, tears and sweat! Proud to see that!" another added.
"Tammy you are the definition of GOALS," a third wrote.
"Wow Tammy you look next level," someone else said.
Others questioned if the photos were even real given the huge difference, however, Tammy has previously shared a number of progress photos showing she managed to build her glutes with a lot of hard work over the years.
Earlier this year she shared a photo of three different stages of her fitness journey over the years, she captioned the snap, "Is it possible to build a [peach] in the gym?? YESSS IT IS & don’t let anyone tell u different."
"Work hard, fuel your body with lots of good food, & you really can make HUGE changes."
Tammy previously told Yahoo Lifestyle she works out between three and five times a week depending on her schedule.
She also shared that those who want to get a butt like hers need to make sure they're "eating enough, pushing yourself with your weights and being consistent".
"If you want to grow your booty you definitely need to be in a calorie surplus to gain muscle, these calories should come from clean nutritious ingredients like lean protein, complex carbs and green leafy veg," she said. "Pushing yourself with your weights also is going to create curves. You need to be lifting as heavy as you can."
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