Kaley Cuoco-Sweeting is not ashamed to say she works hard for her killer body.

The 29-year-old "Big Bang Theory" star covers Shape magazine's October 2015 issue, going topless underneath a plain white button-up and showing off her toned legs in a pair of plain white undies. The actress says she owes her incredible physique "100 percent to yoga."

Shape Magazine

WATCH: A Sweaty Kaley Cuoco Shows Off Her Rock Hard Abs

"It took years for me to figure out what my body needs and that what works for my friends doesn’t necessarily work for me," she admits. "I love being toned and having muscle; it's so sexy and beautiful."

Clearly, her level of fitness takes some dedication.

"I go to a place called CorePower Yoga," she reveals. "One morning I’ll take the Hot Power Fusion class, which is an amazing calorie burner. Or I'll take a Yoga Sculpt class, where we wear three-pound weights during yoga moves. The sculpt classes include 20 seconds of mountain climbing or jumping jacks between the poses, so I get cardio, too."

But it's actually riding her six horses that is not only a good workout, but therapeutic as well.

"I ride horses five days a week whenever I can," she says. "I have six horses, and they have been the biggest blessing in my life. Horseback riding is why I'm so centered, especially in this business. I wouldn't have my career without it."

Shape Magazine

As for her diet, Kaley admits to putting on some marriage weight after picking up some of the eating habits of her husband, Ryan Sweeting, who's a professional tennis player. The two have been married since Dec. 2013, after a whirlwind romance that had them engaged after three months of dating.

"My husband, Ryan, eats so much. I'll cook him whatever he wants…So I make his first dinner, and then he orders a second one from a restaurant!" she says. "When we first got married, it was so much fun to eat like him. We got into this habit we called the bedtime snack. The drawers next to the bed were filled with candy. Eventually, I realized it was mindless eating. I was just doing it because he was doing it, and it was adding hundreds of calories I didn't even think about."

Now, the two are committed to eating healthy together.

NEWS: Check Out Who Tied Kaley Cuoco-Sweeting for the Highest Paid TV Actress of 2015

"Our refrigerator and pantry have completely changed, because we don't eat crap anymore," she says. "No more soda, chips, cereal; we had boxes of stuff that only a 4-year-old would eat. My favorite meal to make these days is gluten-free pasta with vegan butter and veggies. I'm not vegan, nor do I have a gluten allergy, but it just feels better in my stomach."

And she's already seeing the results.

"It doesn't sound like a lot, but I lost six pounds in the last three months," she reveals. "That's a whole jeans size, and we all know how good that feels! I'm the type of girl who’s always had to buy jeans in three sizes because I never know what my body is going to do from one day to the next."

"Everything, from the inside out, has completely changed for me," she adds. "And now, when I look into the mirror and see the positive changes, I don't want to go back to what I was doing. Especially when my husband is like, 'You look amazing!'"

Obviously, we have to agree.

Shape Magazine

Four4Four: Kylie showing too much for fotog?