Guest blogger and award-winning Australian travel writer Louise Southerden finds an unusual swimming companion on the island of Koh Chang.

I'm not entirely sure what I thought when I saw the wiry, bearded man approaching me on the beach that first morning. Sure, he looked perfectly ordinary, with a straw hat, shorts, and a t-shirt. But it was early (too early for the sunbathers who usually showed up after a late breakfast), and he appeared to be carrying a backpack (unlike the typical tourists who did some exercise in the early morning before the heat got too intense).

Nevertheless, I prepared to give him a friendly wave – after all, we were the only people on the beach at that hour – and return to what I had been doing before.

This was my morning routine during my first week on Koh Chang, one of Thailand's largest islands: wake up, walk barefoot along a sandy path to Klong Prao Beach, the island's longest beach, do some yoga exercises in the sand, then go for a swim and afterwards stroll back to my bungalow for breakfast.

I had just sat down and started with some warm-up exercises when my new boyfriend came straight up to me, took a sleeping mat out of his backpack and unrolled it wordlessly just a few centimeters away from my towel.

“Yoga,” he said with an unmistakable Russian accent, and took off his shirt.

I thought he'd just do his own yoga poses while I did mine. But he started copying exactly what I was doing, my sun salutations, my Warrior I and II poses, my pigeon and cobra poses… It seemed a bit odd to me, but I just let it happen.

We then introduced ourselves, despite not speaking a common language. Andrei explained, using drawings in the sand, that he was from Siberia, had been climbing in Krabi, and was now on his way to Cambodia (Koh Chang is near the border) to extend his tourist visa. Then he hugged me tightly, skin to skin. "Shall we go swimming?" I asked.

“Shall we go swimming?” I suggested.

“There, there,” said Andrei, nodding and pointing to a small island on the horizon.

“Ostrov,” he said, “40 minutes.” He held up his watch – a bright orange ladies’ watch with rhinestones marking the quarter hours – and tapped the numbers with one finger.

“That’s too far for me,” I said, explaining with gestures that, unlike him, I didn’t have any swim fins. I offered to swim as far as I could, and we both took off all our clothes except our swimsuits.

As we waded into the water, Andrei put on his orange swimming cap, stuffed some cotton wool in his ears, and took off his Speedos, which he neatly tucked into the straps of his mask behind his head.

"Well, this is something new," I thought: swimming in the Thai sea with a naked Russian climber. It had rained the night before, so the water was thankfully murky. But as we swam out into deeper water, Andrei, playful as a puppy, enthusiastically dove down and swam with his bare bottom beneath me.

I didn't make it to the island – after about 20 minutes I went back to the beach while he continued swimming alone – but I saw Andrei again on the beach that evening. He was watching the sunset and entertaining his two Russian friends with handstands. As soon as he saw me, he ran up to me and hugged me again. "Yoga swimming, Louisa!" Then he wrote some numbers in the sand: a time we were to meet the next morning.

Andrei and I swam together every day for the entire week along the beach, sometimes to dive boats with Nemo patterns that were anchored offshore. And finally, I actually made it to the island – by renting a kayak on my last afternoon on Koh Chang.

Halfway there, I saw something splash. A dolphin? A big fish? Then I spotted the orange cap. Andrei was heading back to the beach after swimming to his "ostrov" for the second time that day. I offered him the chance to hold onto my kayak for a rest.

“Niet,” he said, smiling as he vigorously kicked in the water. Then he waved to me and swam on with the ease of a dolphin—a naked Russian dolphin in Thailand.

Getting there: Buses to Koh Chang depart three times daily from Bangkok International Airport; the journey takes about six hours, including the half-hour ferry crossing to the island. I stayed at the Blue Lagoon Bungalows on Koh Chang. The bungalows cost from 350 baht per night (April–October, low season) or from 500 baht per night (October–April, high season) and are located directly on Klong Prao beach.