From Montpellier in the south of France, David Minetti came to Vietnam in 2003 as a simple tourist, but before long he was back in HCMC to open a gym called the K1 Fitness & Fighting Factory.
As the name suggests, David's gym offers classes in different kinds of pugilism such as kick boxing, Thai boxing, and grappling (similar to Judo), as well as the standard body conditioning and yoga.
"Here we do not teach people to fight but how to keep in shape by doing something different and more fun than biking in the gym," said the tattooed ball of energy that is David Minetti.
"If someone tries to overreach, I stop them. Our students start from five years old. And the most important thing I teach them is not to fight outside."
A regular at the K1 Fitness & Fighting Factory is Truong Trung Dao, a Vietnamese-French art director in HCMC.
"I have been practicing boxing here for three years. I like the service and boxing keeps my spirits up and is good for my health. Thanks to this sport, I have become more disciplined and active," Dao said.
Minetti does some screen acting too and has appeared in several action flicks made in HCMC such as Dong mau anh hung (The Rebel) and My Cyclo.
As though that weren't enough, he also organizes treks in Cat Tien National Park, which covers 72,000 hectares of Dong Nai, Lam Dong and Binh Phuoc provinces and abounds in unique fauna and flora, including many rare and endangered plant and animal species.
A weekend trip to Cat Tien organized by David costs one million dong, which includes transportation by car and boat, equipment use, food and a tour guide, as well as a survival course.
"I teach them how to survive when they are stuck in the forest with no water or food," he said.
Dao, the art director, is one of David's happy campers at Cat Tien. "We never touch anything, plant or animal, if we don't know what it is," Dao said.
"Fear is the most dangerous thing in the forest. David Minetti and the park rangers help us to understand more about the plants and wild animals in the forest. We learn about the bounty of nature and how the different trees and plants can be used. Nature has everything we need.
"Trekking also fosters friendship as we spend time together on the same path and it doesn't matter what you are, young or old, different nationality, whatever," Dao said.
The idea of organized excursions in the wilderness was in David's mind from the start. Soon after he moved to HCMC he began to look for nearby forests that he could visit often.
David's love of the forest goes back to his childhood. "My father started taking me through the woods around Montpellier when I was three years old. He taught me not to be scared of the wild animals but to respect them. He said that if you showed them respect, they would not bother you and might even let you approach them without fear."
Adopting his father's technique, David teaches his trekking clients how to approach the animals in Cat Tien. "They can sense fear in a person and become dangerous. You should submit yourself but not look into the eyes of wild animals. In this way you show that you are lower than them so they feel no need to attack you," he said.
David keeps discovering many kinds of animal in Cat Tien. One time, his boat was moored near a baby crocodile and, when the tour party arrived back at the boat, the young croc seemed agitated by the strangers. Then the mother appeared out of nowhere and got mad.
"The crocodile is very territorial so the mother went after us and attacked us four times by butting our boat on both sides. It even tried to bite a girl in the boat. Luckily nobody was hurt," he said.
David lives in town but tries to get away as much as he can. For him, making the acquaintance of dangerous snakes and crocodiles is a way to relax, just like others do yoga.
It wasn't always so. "One time I saw three-meter king cobra and fled. I couldn't sleep for three nights afterwards," he said.
"I learned about these dangerous animals when I was in the French army. But I do not encourage tourists to copy my actions. There are only five or six dangerous species of snake. Nowadays, if I see a snake, I try to catch it as gently as possible and show it to my friends before releasing it back to the wild," he said.
Minetti said he become more careful about "playing with snakes" after his little daughter was born. Still, he cannot resist the temptation of danger because "I'm drawn to what scares me."
To learn more about K1 Fitness & Fighting Factory and trekking tours in Cat Tien Forest, check out www.k1-factory.com.