For the better part of 25 years I’ve been active – I walk or bike most days, and in normal times my commute is a six-mile round trip on my bike.
It wasn’t always like this. When I was in my early twenties, I gave up a permanent office job to become a bicycle courier. I had barely ridden a bike for years, but it didn’t take me long to develop a little more speed and then endurance.
Over time, in a series of events that surprised me as much as anyone else, my legs developed muscles. And soon after, I got that kind of virtuous glow that I only really saw in very young and physically fit people.
Mine may have been an extreme example, but the health benefits of physical activity incorporated into your daily life are well known.
A Danish study of 30,000 people followed for 15 years found that those who cycled to and from work were 40 percent less likely than others to die prematurely.
Now 52, in my role as a political journalist, I still spend time running between meetings in Parliament – or at least I did before lockdown. But even before the pandemic, I seemed to be spending more and more time at a desk.
For the better part of 25 years, I’ve been active – I walk or bike most days, and in normal times my commute is a six-mile round trip on my bike, writes PETER WALKER. Picture: stock picture
I am all too aware of the risks that sedentary behavior poses to my heart, brain, lungs and bones – among other bodily functions.
But I still look pretty good, so I wanted to know if my more relaxed regimen was keeping me healthy and if it made up for all those hours in an office chair.
To find out how fit I really was, I became a guinea pig, adorned with electronic gadgets that tracked my movements, the time I sat, the heart rate and the number of calories burned.
HEALTH HACKS: Exercising in the cold burns more calories
We have different types of fat cells in our body.
Yellow fat cells store energy from food, while brown fat cells release energy better.
The more brown fat we have, the more energy we can burn during exercise and even at rest.
And according to studies, the body stores more brown fat cells in colder winter months.
This is believed to be because the body uses more energy in cold weather to stay warm (for example, chills).
Theoretically, exercise in the cold triggers the body to produce more brown fat, to burn more energy while resting.
I also underwent a battery of fitness and general physical health tests, interviewing some of the world’s most renowned exercise experts to talk me through the numbers.
Some measurements were reassuring. For example, my resting heart rate is low, about 48 beats per minute, and I remained significantly fitter than average. But others were more concerned.
I borrowed a small stick-on activity tracker of the kind commonly used in college research, which I wore 24 hours a day for weeks. This was just before the pandemic hit, so it captured my (now almost forgotten) normal work pattern.
Every move I made was recorded and entered on a website. While there were occasional sitting periods on the weekends, these were usually interrupted by flashes of activity, such as playing football in the park with my son.
The working days were much more sedentary, despite my commute.
On my busiest days, from about 2:00 p.m. to 6:30 p.m., I was constantly on the clock for nine hours or more of motionless time.
On busy, active weekend days, it can easily take another five or six hours.
Is sedentary life so harmful? Yes, according to research.
A large-scale study that followed more than 120,000 people in the U.S. found that those who sit an average of six hours or more a day were at higher risk of dying from a variety of reasons, including heart disease, stroke, cancer, diabetes, kidney disease, and Alzheimer’s disease.
But regular activity can limit the damage. Even low-intensity exercise, such as standing up or walking around, triggers our muscles to release compounds that help convert fat and calories we eat into energy, rather than store them.
If someone stays seated, this won’t happen – the largest muscles, in the legs and back, go into a kind of ‘sleep’ state called down regulation. This ultimately increases the risk of weight gain and associated health problems.
Another test I took was particularly brutal. Prior to the lockdown, I traveled to Roehampton University to meet sports and diabetes expert Dr. Richard Mackenzie.
There I did a ‘ramp test’, in which I pedaled an exercise bike at ever higher speeds, while wearing a mask that measures how much oxygen you use. It is designed to measure the absolute limit of our fitness ability.
When the results came back my score was 40 – just between ‘good’ and ‘excellent’.
But I had taken the same test a few years earlier and scored 53, which put me in the beautifully named class of ‘superior’.
A Danish study of 30,000 people followed for 15 years found that those who cycled to and from work were 40 percent less likely than others to die prematurely. Picture: stock picture
What had changed? Then my bike ride was about twice as long and I did other activities, including swimming.
It was a wake-up call. But worse was to come. At Roehampton University, Dr. Mackenzie’s team also measured my body fat percentage using a high-tech device called BodPod.
You’re in a box, and it uses air blasts and a complicated algorithm to do the calculations.
For middle-aged men, a body fat percentage of a few points above 10 percent is fine, and anything up to 20 percent is acceptable.
My score was 30 percent. Not only overweight, but obese too.
I was confused. I’m 5ft 9in, and about 10st 12lb, which gives me a body mass index (BMI) score of about 22 – mid-healthy. My waist size is 31 inches, and it has been for the past decade.
So where was all that fat?
One possibility was that the BodPod was giving me a seedy reading, which is unusual but does happen. There is also a chance that I have large amounts of visceral fat with me.
These are fat cells that wrap around internal organs such as the liver and stomach, increasing the risk of things like type 2 diabetes and fatty liver disease. But it’s rare for someone as active as I am to have this ‘hidden’ fat.
Surprised, I reached out to Robert Ross, a leading weight and activity expert from Queen’s University, Canada, for his advice.
He didn’t seem to worry at all. Dr. Ross firmly believes that waist size is the best weight-based measure of health.
Dr. Ross tells me anything under 37in, for men, is fine. For women, it is less than 31.5 inches. I ask him: should I perhaps worry less? He replies, “Amen, Peter.”
The relationship between weight and fitness can be complicated in many ways, not least the idea of ’fat and fit’.
A Spanish study published last week suggested that physical activity alone isn’t enough to reverse the negative effects of obesity on heart health.
But other research has shown that unfit, lean men are more at risk of death than men who are fit and obese.
To me, that alarming body fat reading remains a mystery. Without a full-body MRI scan, I can never be sure.
The good news is that if there is some visceral fat hiding in me, aerobic exercise is one of the best ways to get rid of it, and the effects can start immediately. So with that I’m going to make a bike ride.
© Peter Walker, 2021
- The Miracle Pill by Peter Walker (Simon & Schuster UK), £ 16.99.