Emily Ratajkowski in Bathing Suit Says "City Girls Up!"

Emily Ratajkowski is showing off her new swimsuit collection with the best model for the job—herself! Ratajkowski, 31, shared pictures of herself posing in a park wearing an animal-print bathing suit, much to the interest of people walking by in the background. "City girls 🆙 all new swim for you to look fly in this summer,” she captioned the post. How does she stay so fit? Read on to see 5 ways Ratajkowski stays in shape and the photos that prove they work—and to get beach-ready yourself, don't miss these essential 30 Best-Ever Celebrity Bathing Suit Photos!

1. Happy Weight Gain

Jon Kopaloff/Getty Images

Ratajkowski’s stress manifests itself in weight loss, she says. "When I'm really unwell, I lose so much weight,” she says. “For me, [gaining weight] is a huge game-changer, and it's how I know I'm happy. I think trauma lives in the body. That's my experience."

2. Group Workout Classes

Jamie McCarthy/Getty Images

When it comes to working out, Ratajkowski thrives in a class environment. “I’m one of those people who, if I go to the gym by myself, there’s a 50/50 chance of me actually working out and really pushing myself,” she says. “So the class environment works really, really well for me."

3. Lots of Iron

Arturo Holmes/Getty Images

Ratajkowski prioritizes iron in her diet. “I crave iron so I am definitely not the kind of person who you will find eating a salad,” she says. “I like to keep it really balanced to give my body energy and also be healthy. I cook a lot, so that really helps: You know how much salt and sugar and all of that kind of stuff you are putting in your body.”

4. Mindful of Phone Time

Pascal Le Segretain/Getty Images

Ratajkowski makes sure to keep her phone out of the bedroom for less stress and anxiety and better sleep. “If you can, try putting your phone on ‘do not disturb’ mode or silent when you go to bed,” says SCL Health. “Because even though you may not be on it, the text alerts, game notifications or email buzzes can interrupt your deep sleep.”

5. Black Coffee

Ratajkowski loves black coffee to kick start her day. Drinking coffee black is a great way to get a caffeine boost while keeping calories and sugar at a minimum. “For women, drinking at least one cup of coffee a day is associated with lowered stroke risk, which is the fourth leading cause of death in women,’ says Johns Hopkins Medicine.