When Gordon Sanders takes off his T-shirt for an afternoon run, revealing a chiselled torso and lean frame, it's hard to believe the Texan recently celebrated his 50th birthday. "I feel like I'm 30-something," he says. "I'm in the best shape I've been my whole life."
Considering his active lifestyle, it's easy to see why. When the IT project manager isn't working, he is dragon boating, barefoot running, clocking up impressive speeds strapped to his inline skates or practising kung fu.
Somewhere in between all that, he finds time to be a kettle bell and in-line skate instructor, DJ in a club, and a coach for nutrition, life and even dating.
The secret to his physique and boundless reserves of energy? Intermittent fasting. Sanders goes without food twice a week for 24 hours at a time. "I'll eat dinner, then not eat again until the following dinner," he says.
This unusual regimen started three years ago, after Sanders was struck down by severe food poisoning in China. "I realised how much weight I lost, but not muscle weight. I continued to work out, and started noticing the benefits and muscle gains." A number of books and studies on the subject, including Eat Stop Eat by Brad Pilon, helped to influence his thinking.
Describing himself as an "evolutionary fitness" follower, Sanders says humans should eat and move as closely as possible to the way we did hundreds of thousands of years ago.
"For 99 per cent of the time humans have been on the planet, we haven't had access to convenient foods," he says.
"We had to go without eating sometimes, then we had to have the energy to go without eating and not cannibalise the muscles.
"Take barefoot running," he says, while putting a pair of Vibram Fivefingers minimalist shoes. "It's where we started. Look at children when they run. I have been barefoot running in Fivefingers since 2009, but looking back, I've always enjoyed being barefoot."
His approach enables him to compete with those half his age. In the 18 months since he took up residence in Hong Kong, he has moved quickly up the ranks of dragon boating and in 2012 was voted Men's Rookie of the Year for the Buzz Dragons.
Though he's enjoying the new water sport, Sanders says in-line skating is his true passion - a love he developed in his 20s.
"Skaters have a different attitude to life. One of the premises of skating is that you have to be out of control … You really have to let go and let the skates roll."
What are the benefits of intermittent fasting?
The mental and emotional aspects are quite freeing. By realising I do not have to be dependent on when I am going to eat next, I am able to stay a bit more focused on the tasks at hand. The physical gains are also great, as my body is able to maintain muscle mass while using its fat stores for energy.
Do you get hungry?
I really don't get hungry when I am fasting. I drink lots of oolong tea, puer tea, coffee and water, so this also helps to keep appetite suppressed.
There is a difference between being slightly uncomfortable and hungry. Uncomfortable means that your body is expecting food out of habit; being hungry shouldn't happen for 16 to 24 hours without food.
Where do you find your energy?
I believe that your attitude towards life can actually be a type of fuel for your body and mind. It is empowering to realise all that the body is capable of.
The energy comes from within for all of us, if we just tune in to our bodies. Too many of us respond to outside of our bodies, rather than focusing on our own internal energy.
How can others benefit from your approach to health?
By striving to find balance in our sports and work, both physically and mentally, we should be able to relieve the ultimate limitation on our life expectancy: stress.
Stress is what will kill us faster than anything, and by reducing the stress on our bodies while running barefoot, or finding the flow in skating, or balance while slack lining, we can learn to apply it to our work lives as well.
We can realise that we are all perfect once we find the light within each of us. This light is the fire that gives us energy.
What do you rate as your biggest achievement in life?
Finding out the secret of not being afraid; to realise that fear is caused by things that have not happened, that how I respond to fear is a choice, and that anything is possible.