Jennifer Lopez has her birthday suit ready!

The singer shared an ab-filled gym selfie on Sunday, just a few days ahead of her 49th birthday, which is Tuesday.

“#SundayFunday kind of…,” Lopez posted on Instagram. “Gotta get it in… now let the fun begin!! #birthdayweekbegins”

With her birthday coming up—and an even bigger one next year—the mom of two gets tons of questions about how she manages to look and feel so young.

“Listen, at some point, I’m going to age,” Lopez joked to emmy magazine. “They’ll say, ‘She looks old!’ But, right now, I’m holding it together.”

Even her boyfriend, former MLB star Alex Rodriguez, is consistently amazed by her energy.

“The other day, Alex was across the lawn, and I brought him something, and then I ran away. And he said, ‘You run like you’re 25 years old,’ ” Lopez recalled. “I haven’t stopped that pace, so I’m still at that pace, I guess. When things start aching more, it’ll be different.”

RELATED VIDEO: Jennifer Lopez Jokes She’s ‘Holding It Together’ Ahead of Turning 50: ‘At Some Point I’m Going to Age’

Her intense workout regimen likely helps. The Shades of Blue star does everything from Tracy Anderson classes to boxing to private sessions with trainer — and PEOPLE’s Health Squad member — David Kirsch.

“She’s amazing at everything,” Kirsch, the owner of Madison Square Club, previously told PEOPLE. “She’s genetically blessed, she’s physically gifted with an incredible amount of physical energy, but also this beautiful amount of mental and emotional energy.”

“She’s very connected to her body, and she’s got crazy discipline. And I’m not just saying that — it’s a pleasure to work with someone who is as dialed into her overall wellness as Jennifer is. When she shows up and I get 500 percent. There’s no phoning in the workout.”

With summer in full swing, a lot of us are still on the hunt for the perfect swimsuit. But even when we find a suit we think is flattering, we're not always confident wearing it on the beach, at the pool, or even in our own backyards—afraid that it doesn't conceal what we view as our body flaws.

RELATED: These 13 Women Prove Every Body Is a Bikini Body

Instagram influencer and body positivity advocate Callie Thorpe, however, is here to change our minds. She recently posted a photo with a diverse group of friends and fellow influencers in Mykonos, Greece. In the photo, the women are in bathing suits sporting their cellulite, scars, bruises, and back rolls—and she can't get enough of it. (Neither can we!)

“When I saw the image, I loved how different all our bodies looked together, which inspired my post,” Thorpe tells Health.

“Diversity is beautiful and important and representation matters," she continues. "Sharing these kinds of images allows people to see bodies like theirs that aren’t airbrushed and photoshopped. It reminds people that it’s okay to embrace the things we are told to dislike, like cellulite, spots, and scars.”

In the post, Thorpe urged her followers to enjoy the best things summer has to offer—eat ice cream, head to the beach, or relax on giant pool floaties—without feeling the need to cover up or worry about what they look like in a photo. 

RELATED: These Models Have Completely Different Bodies—but 3 of Them Are Wearing the Same Size Swimsuit

What started out as a sweet shot with close friends soon turned into a viral post that resonated with so many. Fans thanked the Instagram star for her inspiring message of body acceptance, and many said it serves as a constant reminder that the skin they're in is beautiful, just the way it is.

“Body positivity is an important message to share, and it means having respect for all kinds of bodies regardless of beauty, size, abilities or genders," she says.

Is going out for a run, getting into a downward dog, or doing burpees, jumping jacks, and box jumps a pain in the chest? That uncomfortable bouncing is a sign that your sports bra is not supportive enough—something that can not only hold you back during your workout, but can also be bad for your boobs.

Without good support, breasts move up and down during a workout, which overtime can break down the connective tissue in your breasts. A bra that restricts the movement without suffocating you will keep them healthy. The bra should also be made of breathable and moisture-wicking fabric to reduce the risk of any icky bacteria build-up.

We've rounded up three great sports bras for large chests that fit these criteria, tailored to the activities you like to do.

RELATED: The 9 Best Bralettes and Lingerie for Big Boobs

For high-impact training

To buy: Lane Bryant Maximum Support Sport Bra ($70-$80; lanebryant.com)

If you like to run or do a lot of high-impact training, this is the bra for you. It is designed to give you lots of support with full coverage so you can get right down to the nitty gritty. The thick straps won't pinch your shoulders, and they are convertible so you can adjust them into a racerback for stealthy support!

For all your cardio training

To buy: Glamorise Meduim Control Wire-Free Sports Bra ($40; barenecessities.com)

This sports bra was designed for medium-impact training like the elliptical machine, stair master, walking, hiking, and more. It provides full coverage and features adjustable straps so you can customize the fit perfectly to your needs. Best part: There is a closure in the back so you don't have to slither out of a sweaty bra post-workout.

For yoga

To buy: Wacoal Wire-Free Soft Cup Bra (starting at $20; amazon.com)

Made for ultimate comfort, this bra is best-suited for low impact activities. There is no underwire, but the cups are molded to provide enough support. The full coverage design lets you slip into downward dog (or headstand!) without worrying about your girls running loose. You may even be tempted to swap out your regular bra for this super-cozy alternative!