Q What is your secret to looking so fabulous?
A High-intensity running.
When I run the distances I do and go at the pace I have to in order to really challenge myself as a distance runner, it is easy to stay in shape.
Q Has there ever been a time when you were not fit and fab?
A I have lived with osteoarthritis in both knees for nearly 20 years and I have sometimes struggled to balance my training with that.
If it flares up badly, it can stop me doing any sports for a few weeks at a time.
Then I tend to comfort eat, especially junk food and sweets, and particularly when I am not able to exercise, I can gain weight at a rate of 1kg to 2kg a month.
After a severe groin injury stopped me from training for seven months last year, plus the effects of a wedding, honeymoon and the first half year of marriage, I weighed 85kg by the second week of January.
But I am now down to 68kg - as long as I keep up my training, I will stay under 70kg easily.
Q What is your diet like?
A When I am in training, it is lots of cereal, pastas, noodles, fish, soups, salads, fruit smoothies and water - but I still need a cup of coffee sometimes!
I recently discovered calorie- counting apps and this has really helped me focus on what I should and shouldn't be eating.
I need to stay lean and light, but I also need carbohydrates and protein to fuel my workouts... But my wife complains when I get down to my running weight because she says there's not enough of me to cuddle.
MR JAMES WALTON
I need to stay lean and light, but I also need carbohydrates and protein to fuel my workouts. Hence, I use the app to track my diet.
Q What are your indulgences?
A I love Mexican food, pizza, burgers, fried chicken and chocolate - but when I am in training I restrict these to a once-a-month treat.
Q What do you do to relax /how do you maintain a healthy work-life balance?
A Running is often my relaxation. I run to music and think through my day. I work in marketing and many of my best ideas come when I am out on a run.
I like to spend time with my wife watching movies, going for a swim, going out for a walk or playing with our pets. We have three dogs and two cats.
I also play football both for my company and with friends, and coach the Deloitte's ladies football team.
Mr Walton, a British citizen, oversees branding, marketing and business development at Deloitte Singapore. He ran his 20th London marathon last month, finishing in a time of 3hr 30min.
Four days later, he completed the 5.6km JPMorgan Corporate Challenge in a time of 22min and 47sec.
When he was a teenager, he lived in the United States and went to high school there. He went to university in the United Kingdom. He has worked in different parts of the world, including the UK, Czech Republic, Kenya and Nigeria, all with Deloitte, and has called Singapore home for the past 51/2 years.
But wherever he is, he makes it a point every year to be in London to run the marathon in order to raise funds for charity.
Over 20 years, he has raised over $140,000, including more than $10,000 raised this year so far for handicapped children.
He is also the leader of Deloitte Ignite, an in-house programme offering employment, internship and scholarship opportunities to local elite athletes.
His wife, 36, is a full-time student of jewellery design. She works out at the gym, swims and runs. His stepson, 17, is studying at a polytechnic.
Q What are the three most important things in your life?
A Family - my wife and stepson - comes first. Career, not just because it's my livelihood but also because I actually enjoy the challenges it brings being a partner in a Big Four firm. Sports - running and football - are my "outlet" and help to keep me balanced.
Q Do you think you're sexy?
A I've always been shy about my looks. I think a big part of being sexy is confidence, and humour and intelligence play a part. I'm definitely not everyone's cup of tea, but at least my wife finds me sexy!
Q What's your favourite part of your body? And the least favourite?
A My legs - footballer's legs - are strong even by runners' standards. I'm always happy to wear shorts. And I am told I have "piercing" eyes - they change colour from time to time, which is a rare condition. But usually they are somewhere between blue and green.
My teeth are my least favourite. Ever since I was a kid, I had an overbite which makes smiling a bit awkward. I hate smiling for photos.
Q What are your must-dos before and after a match/race/training session?
A I have special playlists on my iPod and iPhone to psyche myself up before a run or a football match.
The night before a big race I will often watch one of my old favourite motivating movies - one of the Rocky movies, Hoosiers, Running The Sahara or Eddie Izzard's biopic Believe - to get me in the mood.
Q What is the most extreme thing you have done in the name of fitness or diet?
A I used to drink a lot of cola drinks - up to 2 litres a day. Then one day I just decided to cut it out. I stopped on New Year's Day, 2009. Most of my New Year resolutions don't stick, but this one has lasted seven years and counting. I haven't drunk a cola drink since and I no longer even have the taste for it.
Q How has your lifestyle influenced others and what do your friends and family say about your active lifestyle?
A I have a few colleagues and friends who got into serious running or took on their first marathon because of me - some who have even run the London Marathon too.
But my wife complains when I get down to my running weight because she says there's not enough of me to cuddle.
Q How extensive is your collection of sports-related paraphernalia at home?
A I have my running trophies dating back to when I was a kid, including Florida state championships for running, and football trophies.
I have more running shoes than I do normal shoes - around 15 pairs in total.
I also have a large collection of sports memorabilia, especially football. I was featured on Mio TV's "Real Fan" adverts last year during their Premier League coverage in recognition of my collection of match-worn shirts and boots from Tottenham Hotspur. This takes up most of my house!
Q Among them, what is your most prized possession?
A From a medal and trophy point of view, I really treasure my 20 London Marathon medals and my trophy for winning The Northface Thailand 100km Duo Relay in 2013 - my first ultramarathon win and one which showed me that even in my late 30s, I can still compete.