Tamara Pettinato in Bathing Suit Asks "Which is Better?"

Argentine star Tamara Pettinato is asking fans what they think of her sartorial choices. Pettinato, 38, shared a picture of herself posing in a white two-piece swimsuit, and a white t-shirt with printed pictures on it. "Which is better?" she captioned the post. How does she stay so fit? Read on to see 5 ways Pettinato 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!

Pettinato uses an exercise/stability ball for her core workouts. "Core exercises train the muscles in your core to work in harmony," says the Mayo Clinic. "This leads to better balance and steadiness, also called stability."

Pettinato loves walking and hiking with her dog. "Evidence suggests that accumulating up to 10,000 steps per day is helpful for reducing chronic conditions such as cardiovascular disease, type 2 diabetes, and some forms of cancer," says John M. Jakicic, PhD. "And more recent evidence supports the benefits of reducing the risk of dementia."

Pettinato does strength training workouts at the gym with a trainer. "Strengthening your muscles gives you the ability to perform everyday activities and helps protect your body from injury," says the American Heart Association. "Stronger muscles also lead to a boost in your metabolic rate, which means you'll burn more calories even when your body is at rest."

Pettinato uses kettlebells as part of her workout regimen, which are great for upper body strength. Using kettlebells can also help improve posture. "With the weight in front of you, your back muscles have to straighten up more to counteract the force of the kettlebell pulling you forward," says Nancy Capparelli, a senior physical therapist at Harvard-affiliated Beth Israel Deaconess Medical Center.

Pettinato partakes in beer every once in a while. Beer can be part of a healthy diet if it's enjoyed in moderation, experts say. "It appears that beer is at least on par with wine in terms of potential health benefits," says UC Davis brewing scientist Charles Bamforth.