
By: Michele Henry Staff reporter, Published on Mon Sep 21 2015
Exhaustion strikes after the squat thrusts and plyometrics — just as the fitness instructor barks at exercisers to bang out “20 more jumping jacks.”
Mustering my strength, I give him 21 because as they say, every step (and jump) counts.
Every step of mine was counted by an “accelerometer” fastened to my hips. The tiny red device recorded every single move I made for seven straight days — during exercise classes, at work, tossing and turning in bed — to count exactly how many calories my body burns in a week.
Why? To find out exactly how much I can eat to keep my weight where it is.
Scientists at Ryerson University’s NExT Lab plan to use this new test, which costs $1,000, to study the relationship between activity patterns and energy balance in overweight and even exceptionally thin people and figure out how we use energy.
Along with the accelerometer, I wore a heart rate monitor at times and recorded everything I ate for the entire week. My results illustrated how matching “intake” with “energy expenditure” — calories in and calories out — is one heck of a challenge. No wonder we’re all struggling to reach our perfect weight.
Those raw data points showed me just how hard it is to balance my daily movements and the scrambled eggs, lettuce leaves and chocolate-covered caramels I consume in a day.
They also showed me how easy it is to tip the balance and not in my favour — a brisk, hour-long walk wasn’t enough to burn off that cup of homemade coffee ice cream I savoured.
Simply attempting to change your weight — by eating less or exercising more temporarily — is often why only 5 per cent of dieters succeed at keeping the pounds off, says associate professor Nick Bellissimo, of Ryerson’s School of Nutrition. The body wants nothing more than to return to some pre-set weight.
That struggle — when you lose the fight and pack the fat back on — is what contributes, over time, to your risk of disease, he says.
Since the same brain centre — the hypothalamus — is responsible for regulating both food intake and energy output, Bellissimo says, this weeklong test may provide clues about how to win at the weight management game.
“We want to figure out how to make the body work for us — rather than against us,” Bellissimo says. “But it’s complicated.”
What is a calorie?
A calorie is the amount of energy it takes to raise 1 litre of water by one degree. In humans, it is the amount of energy stored in food and, how the body uses that energy to power our muscles and metabolic activities.
Total Daily Energy Expenditure (TDEE) is calculated by adding together four measurements:
TDEE = RMR + TEF + NEAT + ExEE
1. Resting Metabolic Rate (RMR); calories burned in 24 hours at rest.
2. Thermic Effect of Food (TEF); calories burned while digesting food.
3. Non-Exercise Activity Thermogenesis (NEAT); calories burned moving around, not including planned exercise. This is where the accelerometer comes in.
4. Exercise Energy Expenditure (ExEE); calories burned during planned exercise. Participants wear a heart rate monitor. It sends information to the accelerometer to help it calculate movement when the hear ticks faster than 130 beats per minute.
The $1,000 test
It’s a weeklong commitment that begins with a day in Ryerson’s NExT Lab and demands that you record everything you eat for seven days. As well, you’re asked to record your planned exercise, the times you take off the accelerometer (only to shower!) and whenever you get into a car (so the accelerometer doesn’t think you’re sprinting.).
But before they strap the accelerometer onto your hips and send you onto your regular activities for a week, researchers calculate your Resting Metabolic Rate (RMR).
Participants spend about 30 minutes lying, as still as possible, under a ventilated plastic hood which captures respiration — both oxygen inhaled and carbon dioxide exhaled. An “indirect calorimeter” machine measures the ratio of O2 to CO2 and converts that information to “energy expenditure,” even indicating what kind of fuel — carbohydrates or fat — your body is burning.
Once that’s done, researchers determine your Thermic Effect of Food (TEF). That is, how many calories your body burns while digesting the food you consume — most online calculators estimate it to be an addition to your daily calorie expenditure of 10 per cent of your RMR.
To do that, they feed you a “mixed-macronutrient meal,” full of carbohydrates, protein and fat, and then it’s back under the ventilated hood for 30 minutes every hour for five more hours, until the O2 and CO2 ratio, which changes when you eat, returns to the baseline RMR.
Who should do the test?
Athletes, aspiring athletes, would-be weight losers who need a kick in the pants and anyone interested in knowing precisely how much they move and how much they burn with each activity over an entire week.
Online calculators, like supertracker, aren’t bad at estimating how much you burn in a day — but they can be inaccurate and misleading, Bellissimo says, especially for the heavier among us. Often, the Internet calculators overestimate calorie burn — leading us to believe we can eat more than we should.
Bellissimo cautions the NExT Lab’s pricey test is best advised when results are given to a dietitian and exercise physiologist, who can help interpret and provide guidance.
My results
Almost every day, I force myself out of bed at 5:30 a.m., schlep, red eyed and grumpy, to the gym for a punishing hour of running or weight lifting or boxing.
After that, I speed walk to — and from — work, adding another eight kilometres to my daily mileage. Though I write for a living (sitting at a desk), it doesn’t stop me from moving around: bathroom runs, walking coffee jaunts, socializing with my colleagues while standing up.
At home, I cook, sprint up and down the stairs in our narrow, three-storey house and wrestle with my two small kids.
You get the picture — I’m active.
So you can imagine my shock at discovering — in my NExT Lab results — that my total daily energy expenditure (that is, the amount of fuel I need to power all that activity) is a measly 1,860 calories.
That’s less than the predicted 2,000 calorie diet the average Canadian, who moves much less than I do, gets to consume in 24 hours. And, 214 calories less than the predicted 2,074 calories online calculators advise me to eat each day (add up those extra calories, and by the end of the week, that’s equivalent to three Burger’s Priest cheeseburgers.
Not only that — I barely burn any calories digesting my food. Where the average person burns an additional 10 per cent of their resting metabolic rate just eating, I burn an additional 8.3 per cent, my results show.
Confession: I’m a teeny person, standing about 4-foot-11. My stature is my problem — and the reason I burn so little.
But still! As the test confirms, I burn a lot of calories by moving — where those who are less active, I’m told, burn most of their fuel through RMR, that is, just being awake.
It also confirmed, that I take about 23,000 steps a day, on average. That’s a lot! And while I don’t eat that much (my “binge” day was 1,980 calories) — it’s clear that, for me, going out for dinner or grabbing a muffin on the way to work is tantamount to waist-line-sabotage, especially, if I don’t kick my activity that day into truly high gear.
Michelle Henry’s Stats
Age: 39
Height: 4-foot-11 (150 cm.)
Weight: 100 lbs. (45 kg)
Activity level: high (average steps 23,269 a day)
Resting metabolic rate (how much I burn in 24 hours, doing nothing at all): 1,082 calories
Today daily energy expenditure (TDEE) = 1,860 calories (the calories I burn, and can therefore eat back)
The online calculator predicted my TDEE would be: 2074. That is 214 calories a day more than what I should eat. At the end of the week, that equals 1,498 calories or almost three burger’s priest burgers, according to Megan Ogilvie’s The Dish.