This Sports Illustrated swimsuit issue cover model and actress was a cheerleader in high school and regularly mixes gym workouts with outdoor challenges like hiking and running on the beach. Last year, she also got into yoga. “She liked that it was challenging and that she felt really good afterward—de-stressed, positive, and happy,” says Tara Stiles, author of Slim Calm Sexy Yoga, who trained and starred alongside Decker. Her favorite moves? Grounding balance poses like half moon, tree and dancer’s pose.