Justin and Hailey Bieber in Bathing Suits Celebrate Her Birthday 

Happy Birthday, Hailey Bieber! The supermodel turned 25 on Monday and her popstar husband, Justin, refused to let the day go unnoticed. The Biebs celebrated his stunning wife by sharing a bunch of photos of her, looking stunning in a variety of swimsuits. How does the catwalk struttter keep herself so fit? Read on to learn about 8 of Hailey Bieber's top tips for staying 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!

Hailey is one of the many stars who are regulars at The Dogpound. While at the workout studio she does HIIT and strength training style workouts. According to a video released this year of her routine she executes sled pulls, pull-ups, kettlebell squats, plank pikes, landmine squats, and mountain climbers like a pro. Read all about it here. 

Hailey isn't a true vegetarian or vegan, but eats as many plants as possible. "I tried a plant-based diet for two months during quarantine," she recently dished to Harper's Bazaar. "I felt great and I had a lot of energy, but it was not for me. I don't eat a strictly plant-based diet and I do still eat meat. I just don't eat a lot of it. I've picked up more fish, greens, and lentils." She eats "a lot of vegetables and fish, not much meat, minimal dairy," she added to Byrdie. "I just feel better when I eat that way." 

Hailey is a big fan of pilates, taking classes at a studio in Los Angeles. "I used to be a dancer, so I love Pilates because it really elongates and strengthens my muscles," she told Harper's Bazaar. "That's probably my favorite workout." 

Hailey likes to box. "I also recently started to box for some cardio," she told Harper's Bazaar. "I found that remembering the combinations and learning how to move your body in boxing has been good for mental health."

Hailey encourages cheat meals. "A really good cheat day" for the star involves "a cheeseburger and fries," she revealed to Byrdie.

Hailey is a big proponent of drinking water. "Monday plans = hydrate + hydrate +hydrate," she captioned an Instagram snap of herself sipping a glass of ice water in her swimsuit 

Hailey is always getting in a good workout outdoors. Swimming, hiking, and paddleboarding are just a few of the activities you can find her engaging in with her husband. 

Hailey likes to workout with her friends. The model has been snapped attending classes with her pals, including TikTok star Addison Rae.