Her solution? Quick 20-minute circuit routine, which she shared on her Instagram page Wednesday night. "On good days, workout. On bad days, workout harder,” she captioned the of herself crushing at what looks like her home gym. “Today’s circuit is what I do when I just have 20 minutes with @lauralizkeller [Sims' personal trainer] to get it in and still break a sweat!”

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Sims' entire workout is made up of seven moves, according to her instagram—and in seven different slides, she shows herself demonstrating them. Here's what her 20-minute circuit workout looks like, doing each move for 45 seconds, and repeating the circuit two to three times:

Jumping jacks
Modified pushups
Tricep dips
Squat jumps
Leg raises
Burpees
Lateral bend and hold (squeezing abs)

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But Sims doesn't stop there—throughout the entire workout, she wrote that she ankle and wrist weights, though she doesn't say exactly how heavy. In her caption, Simms also called out athleisure brand Nylora, who makes her (super-cute) workout set.

As far a Sims' workout routine goes, it's actually really smart to do circuit training when you’re pressed for time, says Albert Matheny, RD, CSCS, of SoHo Strength Lab and Promix Nutrition. “If your goal is to burn calories and wear yourself out during a workout, circuit training is a really efficient way to do that,” he says. Circuit training is also great because it allows you to move on to work other body parts when one area gets fatigued, he says.  “As you’re resting one muscle group, you can start working another group,” Matheny says.

While Matheny says you can “make a circuit training workout out of anything,” he says it’s ultimately best to transition from focusing on one area of your body to another to give certain body parts time to recover in between—and to help you ultimately go harder. “Go from lower body to upper body to total body exercises,” Matheny advises. “It’s really efficient.”  Yup, even if you only have 20 minutes, like Sims. 

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I couldn’t sit by as their futures were threatened by this silent health crisis. And so, I started taking girls hiking on Saturdays. Each time, we walked and talked about things that might be a barrier to them living their healthiest lives. At the same time, my best friend, Vanessa Garrison, was grappling with women in her family dying too early. I knew we had to do something bolder and more transformative.

Read more stories about innovative and inspirational women, check out our Wellness Warriors series 

Vanessa and I set an audacious goal to get 1 million women to walk—to improve their own health, to create a new culture of health for their families, to inspire their daughters, and to take back their neighborhoods. We invited 532 friends on our combined email lists to walk with us.

Walking is the single most powerful thing you can do for your health. Walking 30 minutes a day, five days a week reduces most chronic disease by half. Each time we walk, we also combat loneliness and isolation, and build community, friendship, and culture.

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This is how GirlTrek was born. And not only do we organize walks but we also audit the needs of our neighborhoods as we walk. “Oh, we could put a garden there.” “There really needs to be a traffic stop here.” Or: “This mother has lost her son. Let’s walk and talk with her while she grieves.”

The more we walked, the more word spread. Today, with more than 270,000 members, we’re one of the largest public health nonprofits for African American women and girls in the U.S., and we aspire to reach 1 million members in the near future.

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When we are asked who’s in GirlTrek, we say: It’s rowdy college students, it’s the lunch lady, it’s all the women on the church pew—it’s everybody working together.

Our national team walked 100 miles on parts of the Underground Railroad, inspired by the footsteps of Harriet Tubman. But I find it rewarding when women have their own quiet breakthroughs, like a woman who’s gotten up and walked by herself every single morning for a year, and on the 365th day, she tweets about it.

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As a mom of two, I’d gained weight with both of my pregnancies and never really lost it. So in 2014, a couple of close friends told me over a glass of wine, “You need to take more time to get healthy.” 

The message sunk in. I started making better food choices and running. Over the course of 10 months, I lost 35 pounds. I don’t care much about fashion, so I kept wearing my old clothes until the summer of 2015, when my husband told me one day, “You can’t go to a business meeting in that bra.”

Read more stories about innovative and inspirational women, check out our Wellness Warriors series

It didn’t fit me around the torso anymore, and I couldn’t tighten it. While buying new bras at a local store, I asked the clerk what I could do with all of my perfectly good used bras that no longer fit me. She looked at me and said, “Homeless women need bras.”

Those four simple words changed my life. I went home and called a shelter near my home in the Washington, D.C., metro area. Their response: “How soon can you bring them?”

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I don’t normally post on Facebook, but I felt compelled to mention that I’d just learned of this overwhelming need. Did anyone else have old bras to give away? The shelter had mentioned that women and girls are also frequently in need of pads and tampons, so I asked for donations of those, too.

People shared, and reshared, my request, and it got crazy really fast, in a “lightning in a bottle” way. Within two days, my Facebook group, Support the Girls, was born. A few months later, my husband made a website to keep up with the demand.

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By that time, I’d made it to the shelter, and I had collected more than 1,000 bras and more than 7,100 pads and tampons. It didn’t make sense to stop there. Today, Support the Girls has nearly 60 affiliates across the U.S., as well as around the world. We’ve donated around 5 million products, including mastectomy bras, prosthetics for women going through cancer treatment, binders for trans boys and men, menstrual underwear, and menstrual cups. We’ve donated to Chicago public schools and the Indiana Department of Corrections, and provided supplies during and after natural disasters like Hurricanes Harvey, Irma, and Dorian.

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