Who's the hotter Hemsworth? Australian actors Chris Hemsworth and Liam Hemsworth showed off their buff bodies while vacationing together in Costa Rica Jan. 21. The two were went surfing with their father, Craig Hemsworth, and their actor brother, Luke Hemsworth.

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Standing tall at 6-foot-2, Chris showed off his pronounced pectoral muscles while carrying his surfboard along the shore. "It wasn't until Thor that I started lifting weights. It was all pretty new to me," the 29-year-old actor once told Men's Health. The Cabin in the Woods star also revamped his diet to include more protein sources, vegetables and fruit. Said Chris, "Eating when you're not hungry and taking in that amount of food is exhausting."

Liam — who brought along his 20-year-old fiancee, Miley Cyrus — surfed competitively for five years beginning at age 13. "Every day, before and after school. I wanted to surf for the rest of my life," the 23-year-old Hunger Games actor once told Men's Health. "It's what all my friends did — I even had it as a subject in school for a number of years. They teach you all parts of the surfing industry. How to judge surf heats, that sort of thing." (Check out more sexy shirtless photos of the Hemsworth brothers via PopSugar!)

In addition to surfing, Liam works out with a personal trainer (a former Navy SEAL) five to six days a week. According to the Empire State actor, his exercises include throwing tires, climbing ropes — "all sorts of unorthodox stuff that you wouldn't normally do in a gym," he told the magazine.

Tell Us: Which Hemsworth brother looks sexier with his shirt off?