Lord willing, in 13 weeks from today I will hop on a plane for Hawaii, where I plan to spend 9 days surfing. This will be my 10th trip to Oahu in as many years. I spent the morning prepping for all the paddling I'll be doing by lifting and then getting in my 20,000 steps.
For surfing you need a really strong core, arm strength for the pop up, and a strong back and rear delts for all the paddling you have to do, especially at Diamond Head.
Really, surfing is a full body activity. You're mostly paddling and waiting, but once you're up and riding you're recruiting the muscles in your legs and core. To increase your time out in the water you'll also need to focus on cardiovascular fitness. Even in Hawaii, we have small and flat days when you might catch only one or two waves while you're out for 3 hours. But I'm never happier than when I am in "my" element, the ocean, where I was born and bred.
Of course, the best exercise for surfing is surfing. Keeping my eye on the Virginia Beach surf report!