Celebrity Fitness Secrets: 10 Stars Reveal the Fun Workouts They Swear By

Apart from having gorgeous skin and hair, "Girls" actress Allison Williams is also known for having a seriously svelte body. Her secret: fun (and effective!) group fitness classes. She recently shared the two components to her fitness routine with Shape Magazine: weekly SoulCycle and Core Fusion classes. (Reuters)

It’s no secret that dancer-turned-actress Julianne Hough is one fit lady. As she told Self magazine, she’s picked up running (despite being somewhat asthmatic) and turns TV time into a mini workout by exercising while she watches. Plus, based on this video of herself doing some impressive tumbling on a trampoline, it’s obvious that she has fun with her fitness. (Reuters)

She plays an athletic swimmer in "Pretty Little Liars," so it seems totally fitting that Shay Mitchell is also super active IRL, too. When it comes to fitness, the actress seems to do it all: she runs, dances, hikes, shadowboxes, takes cycling classes, and more—she’s even into rock climbing! (Reuters)

Nina Dobrev’s character on "The Vampire Diaries" may owe her strength to the supernatural, but the actress works hard for her health. According to Shape Magazine, her fitness formula includes surfing, hot yoga, total-body workouts with her trainer Steve Moyer (of The Moyer Method), and more. (Reuters)

One of the three beautiful models to grace this year’s Sport’s Illustrated swimsuit issue, Chrissy Teigen obviously keeps a very fit form. She balances the occasional fried chicken dinner with barre-based workouts at Physique 57. (Reuters)