Five months into my all-in training for the 2020 Hong Kong Marathon and the physical and mental changes are rolling in like waves.

One hundred and sixty days of sobriety have morphed my body on every level: sleep cycles, skin, weight loss, general anxiety, cognitive function and even my wallet. There have been no setbacks and I’ve found new physical gears I didn’t know existed. I got the chance to hang with some university-level cross country runners back in Canada, putting my body to the test for the first time, and didn’t embarrass myself, a definitive win in my books.

To be frank, I’m crushing life right now, couldn’t feel better and I’m contemplating making my sobriety and training regime a permanent thing. I can’t fathom going back to the old ways. I would be going backwards when forwards is the new mantra. I’ve installed a new operating system on my hard drive, and can only imagine the person I might become if I stay on this path.

I’ve also been given the chance to train under physiotherapy clinic Joint Dynamics’ Erwan Desvalois, an accomplished middle-distance runner from France. Desvalois has me on a weekly running plan which also includes some strength training, but first he did what all good coaches do and calculated a term I’m hearing a lot lately: one’s “running economy”.

Joint Dynamics coach Erwan Desvalois is helping turn this Post reporter into a running machine. Photo: Handout

First was my GAIT analysis and 3DMAPS to help iron out my running stride as much as possible, then some first-class shoes from Hong Kong running guru Peter Hopper.

Then it was down to the nitty-gritty, a VO2 max test (maximal oxygen consumption) which had me on a treadmill with a heart rate monitor strapped to my chest and an oxygen mask on my face sprinting until I was seconds from blacking out. I scored a 48.8, which Desvalois said was “excellent” for my age category (36 at the time). However, I hampered myself by running a 10k in the morning, so I’m keen to do it again and see if I can bump that number a bit.

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“Above 52 would be superior,” said Desvalois. “Under 46 would be good, under 42 would be fair and under 38 would be poor. World-class athletes can score 75 to 85 but surprisingly some runners have shown a 66 VO2 max whereas they can run a 3:35 1,500 metres, which is, at the end of the day, the entry mark for the Olympic Games. So, once again, it is the example that their running economy compensated for their ‘lack’ of maximal oxygen intake.”

Desvalois explained VO2 using an analogy with two cars. Both cars have the same engine and the same amount of petrol, but one has to race three hours with the windows open, one flat tyre on the left, one wheel misaligned on the right and loose bolts all over. The other has no issues. Basically, runners who have to work less and have better performing bodies tend to win more races, as simple as it may sound.

He said athletes have pretty consistent scores throughout their careers. “It is mostly based on your genetics and most scientists agree that it can't be improved more than 5 to 15 per cent, sometimes it does not even vary.”

A deeper look at my VO2 max score. Photo: Handout

What Desvalois means by one’s “running economy” is a tabulation of a number of factors including the VO2 max, but the marker he said most accurately predicts it is a Maximal Aerobic Speed, or MAS, test. For this, we headed out to the track at the Siu Sai Wan Sports Ground early one morning to beat the heat.

The test was simple, six minutes around a 400-metre track as fast as I could. This meant trying to pace myself so I could stay as close to my threshold as possible. By the end of it, with Desvalois cheering me on, I was pretty close to heaving up my breakfast, but luckily avoided disaster with some deep breathing.

My score: 16.30km/h, which Desvalois said is “pretty good” for my age. Now with still more than five months to go to the Hong Kong Marathon, he said I can definitely improve as we ramp up my training and start to pack more kilometres into my regime.

Ground control to Major Tom? In the Bod Pod getting my body fat tested. Photo: Erwan Desvalois

The final test was quite unusual, my body fat, which required me to strip down to my underpants, put on a swim cap and hop in a Bod Pod machine that looks like a futuristic spaceship. I came in at 10.7 per cent, which is well within the zone of elite athletes.

I’ll credit my low score to two things. First, being able to stomach the Hong Kong heat and go for runs in the middle of the day to sweat off the weight; and second, a diet that includes a lot of fasting and basically eating one meal a day with various snacks in between. I’m not super strict, but I find eating less allows you to be a bit more flexible on the intake, although I am trying to stay away from sugar as much as possible.

Desvalois said my score is “quite low but that doesn't surprise me as you are a runner and we all burn a fair amount of calories”. He also noted the Bod Pod is easily the most accurate way to calculate body fat, so we know this number is right on the money.

I’m shooting for a personal best in February at the 2020 Hong Kong Marathon. Photo: Jonathan Wong

This autumn I’m taking on the Victoria to Peak Challenge, an 11k vertical climb on October 1, and the Oxfam Trailwalker with three fellow Canadians, a 100km epic hike on November 15-17. Desvalois has me building and tapering, making sure I don’t peak, plateau or burn out, all with the final goal of being in the best shape of my life come February 9. Every week or so, as I continue to build my running economy, I can feel my body adapting to new levels of fitness.

It’s a remarkable feeling, intoxicating, knowing one’s limits can be pushed to heights you once thought unreachable, with the right coaching and guidance.

I’m hooked on this new drug, the runner’s high is the only vice I need these days.