How a VO2 max test showed me the true meaning of fitness

Part 1: A gruelling assessment
Part 2: Running tips for race day
Part 3: Across the finish line

Part 1: A gruelling assessment leads to unexpected results

The best part of my VO2 max test is the view, and it is not inspiring. I look out at a parking lot on the west side of NAIT’s Main Campus and, beyond that, Edmonton’s City Centre Airport lands, vast, empty and brown.

But compared to where I am, it still looks pretty good, because the VO2 max test is, by design, a state of prolonged suffering.

It’s being administered by Personal Fitness Trainer instructor Dr. Tim Just, who’s measuring how much oxygen my body can use during intense exercise. I’m on a treadmill set to 12 kilometres per hour, my nose and mouth are covered by a mask resembling a plunger, and my chest is banded by a heart rate monitor. Every two minutes, Just raises the elevation by 2%.

“Doing great, Scott,” he says as he watches data pile up on the computer that’s monitoring the operation. The treadmill climbs another notch, like a torturer turning a crank on the rack.

But the torturer isn’t Just. It’s me.

But the torturer isn’t Just. It’s me, motivated by a single question: What is this body capable of?

To some extent, I know. I started running a decade ago, initially attracted by its simplicity: lace up, pick a direction, and leave your stress in the dust. But after my first half-marathon in 2011, I felt more confident and competitive with each passing year – to the point where I’d set a goal of a top-three finish within my age category in the half (21K) at the 2018 Edmonton Marathon, which I’d missed by two spots the year previous. And I wanted to do it despite surgery to repair veins in my leg the week following my VO2 max test.

Just, however, saw a bigger goal. Using the tools and theory of the classroom, he was gathering information that would make clear a link between fitness and long-term health that often goes missing in fad diets, protein shakes and, yes, long-distance running. Ideally, Just wanted me to look beyond race day.

“Still good?” he asks. Lungs burning, legs growing heavy, I nod. The treadmill ratchets up to 8%. Ten seconds later, I give up and tap out, reaching a physical limit that, really, is only a starting point.

The meaning of fit

Cardiorespiratory fitness, even when measured by a spirit-breaking VO2 max test, could be defined as the ability to do any sustained activity – walking to a bus stop, mowing the lawn or shovelling the walk, playing with the kids – without gasping for breath. It reflects how efficiently the circulatory and respiratory systems supply muscles with oxygen, and how well those muscles use it.

It’s also something of a fortune teller. Cardiorespiratory fitness improves the effectiveness of insulin, body composition, blood pressure and much more. Because of that, fitness and lifespan are linked, as one review of existing evidence shows. When mortality starts calling in loans, it’s like money in the bank.

“For the general population, we want to get [VO2 max] as high as possible before age catches up,” says Just.

running shoes blown-out toeAt my age, 42, mine’s in decline (when I did this test five years earlier, the results were irritatingly better). But it’s still an important metric, in that it’s a point of peak oxygen use, when the body’s engine revs to near-breaking point. Just works back from there, knowing that fatigue sets in ahead of this limit, sooner than later for most of us.

An elite athlete can run at 80% to 90% of their VO2 max for a long time, he tells me. Then he breaks the news: I am not an elite athlete.

"Some people take this the wrong way: [you’re] a weekend warrior type."

“Some people take this the wrong way: [you’re] a weekend warrior type, where you’re working really hard two or three times a week to improve performance. You’re not just running for health. You’re looking to compete in an event, which is good, because it has all these benefits associated with it.”

Whether those benefits include that top-three finish, Just doesn’t know.

“That’s an ambitious goal. Let’s see where you’re sitting and start working towards it.” He pauses to count back from race date: Aug. 19, 2018. Minus two weeks’ recovery for surgery, Just sees eight weeks of training.

“That’s plenty of time to improve,” he says, sounding almost believable.

Down the rabbit hole

scott messenger 2017 half-marathon Edmonton Marathon medal“How the body adapts has always fascinated me,” says Just. “I just love going down that rabbit hole. With training, especially endurance training, it’s really methodical. You’ve got the numbers you need to hit, you’ve got a specific plan for getting you there, and it’s about how scientific you can be in applying that to your own life.”

Given its myriad variables, increasing VO2 max will take more time and energy than I will ever have. Instead, Just wants to boost my anaerobic threshold – that point during exercise when cramp-inducing metabolites such as lactate build up faster than the body can clear them. After analyzing the data, he figures that’s 70% of my VO2 max, or a heart rate of 160 to 165.

To raise that threshold, Just creates a plan to force my body to meet new demands, and to build on training I'd started before the surgery.

After two weeks of rest and light exercise, the first three weeks of training involve alternating between short, slow runs at a mildly winding pace, and ones punctuated by chest-heaving sprints. He slots in weekly long runs, 10 to 18 kilometres, also at an easy pace. Because we’re short on time, there are very few rest days.

Physiologically, the idea is to widen the network of oxygen-carrying capillaries, as well as strengthen ligaments, muscles, bones and blood vessels before upping the pace. “Right now your short-term goal might be to get back into your groove,” says Just.

When I finally ease into training after surgery, sustained speedy runs aren’t an option anyway. My legs feel unfamiliar, as if trust between them and me needs to be re-established.

My legs feel unfamiliar, as if trust between them and me needs to be re-established.

Which, probably, is a good thing. My previous, self-designed training plan was to run fast, period. Just’s data, however, gets me thinking about how putting down one foot in front of the other, done properly, can build a better a body, not just a faster one. Slow, for once, makes sense.

In comparison to nailing a personal best, logging the miles needed for long-term functional fitness is about as exciting as that parking lot I stared at during my VO2 max test. But without it, pulling up in a Ferrari (or at least, say, a Corvette) isn’t even possible.

Just believes that running is its own reward. Inherent in his approach to training is the idea that it’s a privilege to be able to explore and attempt to improve our physical capacity. The journey’s the thing, because there really isn’t a destination. Except when there’s a finish line, of course.

As for a top-three finish in my cohort at a half-marathon?

“I’m not saying you shouldn’t try,” says Just.

We’ve done the math. Now let’s see what this body can do.

Part 2: 5 running tips for race day

jelly beans - the perfect long-distance running snack?Around week four, when the miles began to pile up in the half-marathon training plan that Tim Just made for me, a link developed between jelly beans and self-doubt.

Scrambling to find a just-in-case energy source for long runs, I took to raiding the kids’ candy stash for five or six “gourmet” beans. While I could manage less than 12 or 13 kilometres jelly bean-free, distances approaching the 21.1K of a half-marathon were marked by mixes of lemon-lime, cola, cotton candy, popcorn and other unlikely pairings.

Not convinced I could make it through without, I checked with Just to see if I was on track. The Personal Fitness Trainer instructor offered me five tips, and passed no judgement on my questionable sugar intake – other than to say that, in all likelihood, it wouldn’t hurt to leave them for the children.

1. Focus on footwork

Early in the training program, Just recommended exercises to improve running economy and make movement require less energy. “A lot of people try to run faster by taking longer strides,” he says. “It’s more efficient to take shorter strides.”

Count strides and aim for consistency (I shot for 90 right-foot strikes per minute). Eventually, the body will default to that cadence, says Just. Be patient with this, he adds. Developing economy “is a lifelong thing.”

2. Trust the plan

“We train hard so you can race easy,” says Just (pictured below). In one run, he had me cover more than the distance of a half-marathon. In another, he split an 18K into slow, medium and fast segments. The latter was a five-jelly-bean run with two unsanctioned one-minute walking breaks.

“We train hard so you can race easy.”

Just said not to sweat it (I did, though, literally. And a lot). He took the struggle to mean I was adapting to the anaerobic threshold he’d hoped for, that my body was getting better at exerting itself while clearing out rapidly accumulating, performance-limiting metabolites. Trust the training plan despite any concerns. “The idea is that you peak at race day.”

nait personal fitness trainer instructor Dr. Tim Just3. Adopt race routines

Start long training runs close to the same time of day as your race. Eat the same way, too. Just recommends a balanced meal the night before, including whole grains, followed by something easy to digest at breakfast.

As for water, stay hydrated during training runs. How much you drink is up to you, says Just, but he points out that an inactive person needs about two litres of fluid a day. During exercise, you'll need to replenish 0.5 to one litre of water per hour, weather dependent.

4. Don’t change a thing

Once you learn how your body will react under certain conditions, don’t introduce new ones. If jelly beans have become a psychological crutch, don’t kick it out from under yourself. “Race day is not a day to experiment.”

“Race day is not a day to experiment.”

5. Look beyond the race

Despite being wholly focused on a single event, looking beyond it can lead to a positive outlook. The finish line of one race is just a starting point for the next.

This is particularly helpful if you’ve set challenging goals.

Just’s plan crammed about 12 to 18 weeks of training into eight due to my early-summer vein-stripping surgery. Is a top-three finish in my age bracket still a reasonable expectation? While we needn’t contemplate failure, Just gave the impression that we should be flexible in how we define success. “[The race] should be for fun. You’re going to do the best you can.”

And then, perhaps, better in the next one.

“Whatever happens,” he says, “you’re more than young enough to improve. You’re going to run well but I would contend that in a month you’ll be able to run even better.”

Part 3: Across the finish line

scott messenger, 2018 Edmonton Marathon, half-marathonIt was, almost miraculously, a beautiful day for a race.

During the week before the 2018 Edmonton Marathon, the capital was blanketed by smoke from the British Columbia wildfires. But that August Sunday morning, the air turned suddenly clear. It was cool, still, refreshing, and it seemed to put a spring in everyone’s step. Just after 8 a.m., nearly 2,000 runners burst from the starting pen in front of the Shaw Conference Centre, like birds from a cage flung open.

I’d seeded myself well back from the sinewy runners who’d clearly lead the pack, but couldn’t resist the urge to bolt – despite trainer and NAIT Personal Fitness Trainer instructor Tim Just’s advice to start conservatively. The conditions were too perfect not to chase that goal of a third-place finish in my age category. So I did, courting disaster.

After nine quick kilometres, I began to lose ground, running each of the next five an average of 45 seconds slower. During the last seven, however, I shaved off 20 seconds apiece, approaching the pace a smart runner would have maintained the entire race.

In the end, I crossed the finish line with a personal record for a half-marathon, even if only by a few seconds. I knew I’d arrived among an early cohort of runners. But, as I poured a bottle of water over my head and walked down what seemed a hummingbird heart rate, a question remained: Did all that training pay off ? Did I clinch third place?

I headed to the timekeeper’s kiosk for the answer.

Results versus rankings

nait personal fitness trainer instructor Dr. Tim Just administers a VO2 max test for runner Scott MessengerWhen I saw my name roll up in the real-time rankings, the answer seemed a resounding ‘no.’

Fourth – almost a minute-and-a-half behind the number-three runner, who raced identically (fast, lag, recovery), apart from running every kilometre four seconds faster on average.

I headed into one of the conference centre’s cavernous and nearly empty halls for the event’s brunch. As I ate a lonely meal of English muffins, scrambled eggs and black coffee, I tried, and mostly failed, to find satisfaction in the personal best.

A week later, however, Just helped. Another VO2 max showed that everything went almost exactly according to plan – his plan. Regardless of rankings, the experiment was a success.

Regardless of rankings, the experiment was a success.

“There were a lot of confounding factors,” he says – among them my vein stripping surgery earlier in the summer, a compressed training schedule and weeks of smoky running conditions. “A lot of things could have forced us to deviate from our plan. [But] I got the results I was shooting for.”

As proof, he highlighted three key metrics:

  1. Increased VO2 max. Just describes VO2 max as “how well your body takes in oxygen, transports it and then turns it into energy.” Over roughly two months of training, we achieved an eight-per cent increase (with about two per cent of that owing to losing a kilogram of fat during training, Just estimates). That is, we succeeded in changing my body on a fundamental, even cellular, level. It met increased demands for oxygen by threading new capillaries to muscles. Within those muscles, says Just, mitochondria, the tiny but mighty power generators of our cells, probably increased in efficiency and even number. “You muscles are just more finely tuned for turning that oxygen into energy.”
  2. Increase in anaerobic threshold. At this threshold, CO2 output begins to outpace O2 intake, as the body works to eliminate performance-limiting metabolites that build up from intense exercise. In my previous test, this imbalance hit at 70% of VO2 max, the body’s capacity for using oxygen. In the post-race test, this didn’t happen until 86%, meaning it took longer to tire out. The punishingly long training runs were key. “Those are the ones that hurt,” says Just. “That’s what pushes this up.”
  3. Decreased heart workload. At one point of high intensity in the recent test, Just saw my heart rate drop four beats per minute compared to the previous test. What’s more, we reached a maximum rate eight beats per minute higher at the second test’s end. “Your heart got stronger,” says Just. “It got better at sending blood where it needed to go, with fewer beats.”

But even with the positive results, Just’s attitude suggested there were no laurels to rest upon. It reminded me that, personal best or not, I’d ultimately placed unremarkably.

“We saw a huge change in two months,” he said as he handed me copies of the data – a cold distillation of hundreds of kilometres travelled by foot alone. “But there’s a lot more to do.”

The next (few thousand) steps

Other than to tell me how far to run, how fast and when, Just never tried to influence my goal. He showed me a path and the science underlying it. Then he left it to me to decide whether to chase that goal.

Don’t try this on your own

At the risk of sounding boastful, the compressed training program Just prescribed for our “experiment” isn’t one he’d give everyone.

The first VO2 max test showed my fitness to be relatively high for my age, and Just reviewed my previous half-marathon times. What’s more, he didn’t proceed with the most intense portion of the training until I’d got the blessing of my vascular surgeon.

With these reassurances, “I felt comfortable giving you this tough program and seeing how you could hold onto it,” he says. If you’re looking to make similar gains, consider working with an experienced trainer, and make sure he or she has your heart’s best interests at heart.

But in saying there was more to be done, he suggests the path didn’t end at that half-marathon race. It just forked.

The path didn’t end at that half-marathon race. It just forked.

One direction offers easy travelling, but a less appealing destination. Run moderately three or four days a week and “it’ll bring you into old age nicely, and avoid injury,” says Just.

The other direction means tougher going, a trip that will take much longer than a couple of months. Where it leads, who knows. But it promises, to eventually resolve that question that, in my case, Just seemed to feel we hadn’t yet answered: What is a human body capable of? “If you want to be competitive and push a little harder,” he says. “You’ve got room to do that.”

Old age sounds better than its alternative, but it just waits there, pretty much indifferent to whether or not we actually show up. A good goal makes things interesting. It stays a few (or many) steps ahead, and forces you to change, adapt and grow as you try to close the gap.

Even if that never happens, that sounds like a pretty good run to me.

Scott Messenger lamely attempting to stretch

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