Measuring Ourselves Sick

From a 400-year-old weighing chair to the fitness apps that track our every move.

This month I had to download a gym app to buy a day pass to work out. In the gym’s dark mood lighting and techno music, I struggled to find the squat racks and found it even harder to find someone not plugged into a phone. People were tracking reps, sets, videoing their form and logging calories in between movements.

The gym app’s tagline was ‘rewarding healthy obsessions,’ which gave me pause for thought. The word itself comes from the Latin, obsessio, which means a “siege,” “blockade,” or “a blocking up.”

Where did our ‘healthy obsessions’ come from?

In late March 1711, the British periodical, The Spectator, published a letter from a man who had spent three years in a chair. The man had read, eaten, drunk, and even slept in the chair. “It may be said,” he wrote, “for these three last Years, to have lived in a Pair of Scales.”

This, as you can guess, was no ordinary chair. The chair hung from springs and weighed whatever was in it, which was usually our would-be scientist. With a level of obsession that echoes the modern age of Fitbits and calorie counters, he didn’t eat because he was hungry; he ate based on the feedback from the chair. After dinner, he walked until he had sweated off five ounces, as measured by his weighing scales.

Joseph Addison, who printed the letter, and even perhaps wrote it, popped in a line from Virgil to top things off. Aegrescitque medendo, or ‘he grows sicker with the cure.’ He later added an epitaph supposedly from an Italian hypochondriac… Stavo ben, ma per star meglio, sto qui, which roughly translated as “I was well, I wanted to be better, here I am.”

The Man in the Chair

Addison’s correspondent had borrowed his idea from Santorio Santorio, an Italian physician who had been dead for seventy-five years.

Born in Capodistria in 1561, then part of the Venetian Republic, Santorio became a professor of theoretical medicine at Padua. He knew Galileo Galilei and was known for his fondness for gadgets. He built a pendulum for measuring the pulse, a special thermometer to test on his patients, and of course, a chair.

Since Galen, doctors had believed the body leaks an invisible vapour, perspiratio insensibilis, steadily through the skin. It was taken as common knowledge but never tested until Santorio.

Driven by a stubborn determination to find out the answer, Santorio suspended a chair from a steelyard, a large balance used by merchants, and spent about thirty years weighing himself. He weighed himself before and after meals, after movement, after sleep and after using the toilet. The visible stuff barely mattered to his weight.

In 1614, he published Ars de statica medicina, where he reported that of eight pounds eaten and drunk in a day, about five left the body completely unseen. Oh and his major piece of advice from a life of obsession? Put in what you’ve lost and no more. Ta-da!

Weighing the Smoke

Before the chair, this idea of insensible perspiration was just a belief but after it, it was a number that you could cite.

In 2018 Teresa Hollerbach, built a working replica of the chair and credited Santorio with bringing measurement into physiology, which wasn’t bad going for a man sitting on a plank.

His chair was blunt. It couldn’t tell sweat from breath, so everything that left invisibly went down as one loss. Some of that missing weight came from carbon dioxide breathed out through the lungs, which nobody could identify until Joseph Black in the 1750s. A century later, French physiologist Claude Bernard compared this whole approach to working out what happens inside a house by weighing what goes in the door and what comes out the chimney.

Addison’s correspondent took Santorio’s chair and turned it into a rulebook for living. In his reply, Addison described a gentleman who ignored “those natural Sollicitations of Hunger and Thirst, Drowsiness or Love of Exercise” and governed himself “by the Prescriptions of his Chair.”

The wonderful thing is that, after three years of measuring almost everything, the man admitted that he was in “a sick and languishing Condition.” He had become so obsessed with preserving his health that he’d forgotten how to live. Santorio had used the chair to investigate the body. Addison’s correspondent had come to trust it more than the body it was measuring. Sound familiar?

Sicker With the Cure

The chair, and its control over us, never disappeared. It just changed shape.

During the 1890s, Wilbur Atwater, a chemist in the USA, built a respiration calorimeter. This was a small sealed room where volunteers lived for days at a time while his staff weighed and measured everything that went in and everything that came out. Right down to the air they breathed.

If you’ll forgive my flippancy, it was Santorio with added plumbing. Atwater’s experiments revolutionized the way we think about food. The calorie had been around before him, but his work helped make it a staple of nutrition. His sealed room will be re-enacted on Netflix any day now, presumably.

Atwater’s figures are why food labels still say four calories a gram for protein and nine for fat. His room is the reason you can stand in your kitchen weighing a satsuma and patting yourself on the back for eating a low-calorie snack.

That’s most of what I would class as the ‘modern chair.’ A large number of fitness fanatics (myself included) slap calories into MyFitnessPal and check our watches every few hours to check how many steps we’ve taken. 10,000 a day or else, am I right? That actual target came from a Japanese company named Yamasa, who sold a manpo-kei pedometer in the 1960s. The number came from a Japanese walking campaign and became a selling point for Yamasa’s pedometer. It was never a scientifically established threshold for good health. Yup.

In 2019, I-Min Lee’s team at Harvard tracked around 16,700 older women and found that the association between step counts and lower mortality levelled off around 7,500 steps a day. Calories, by the way, are not much better. In the US, FDA rules allow the measured calorie content of packaged foods to exceed the stated figure by up to 20%. And don’t get me started on restaurants. If you have ever worked in a kitchen you will know, with the best will in the world, that chefs cannot guarantee a set calorie count.

Did we apply the same amount of butter or oil to each pan? Did we have exactly 80 grams of chicken or 200 grams of potatoes? Sure we could do all of this but given the temperaments of most chefs I know, it would be a recipe for breakdowns. First the plates as chefs flung them against the walls, and then the chefs themselves.

My point is that you can log every single gram you eat for a year and still be guessing. None of this means the numbers are useless. I track my lifts, my workouts and, occasionally, my food. They’re useful things to know. The trouble comes when you start treating the number as more reliable than your own experience.

Sleep is no different. In 2017 Kelly Glazer Baron and colleagues used the term orthosomnia to describe patients who had become anxious about perfecting their sleep. They were seeing people so concerned with what their sleep trackers were telling them that the tracking itself had become part of the problem.

You don’t need to be Steven Bartlett, who recently incurred the internet’s anger for complaining that three glasses of wine ruined the next three days of his life, to feel this. You wake up feeling fine, check your smartphone, and see that it’s logged you at 5 hours sleep when you were in bed for seven. Or that your 10,000 steps didn’t count because your Fitbit died or, as happens to me, you didn’t hit your step count because your pedometer ignores the 90 minute cycling commute. Addison’s correspondent used a chair to quantify his life. A lot of us now use our phones.

So why is fitness so attached to all of this? I think it’s because quantification makes something difficult to sell look easy to prove. Feeling a ‘bit better’ in four months is vague and slow. It is impossible to photograph and hard to measure. Numbers, on the other hand, feel tangible and real. You can compare them.

Physical culture worked that out a century ago. Eugen Sandow’s correspondence courses in the early 1900s wanted your measurements before they’d prescribe anything. The inches you added to your frame were how you knew the course worked. One Irishman, F.A. Hornibrook, wrote about measuring his biceps every day for months, to track the impact of Sandow’s courses. Charles Atlas built an empire on the ninety-seven-pound weakling, which was a number every reader could picture. Gyms still sell body-fat scans and before-and-after photos taken in the same horrible lighting to convince people to sign up.

What’s changed is that now the numbers never stop. Whoop gives you the strap and charges you a membership, whereas Oura introduced subscriptions with its third-generation ring in 2021. Phones can now track your steps and a watch tells you how your heart is beating. Hornibrook had to get his tape measure out every morning. Now a ring reports every morning, and every morning there’s something to fix from your sleep score to your resting heart rate.

MyFitnessPal claims over 280 million users around the world. In a recent press release Whoop claimed that, on average, users check the app more than eight times per day to check sleep, recovery, and strain metrics. These businesses run on you checking. A customer who feels fine and stops looking is a customer who cancels their subscription.

I grew up in an era of fitness where ‘what is measured is managed.’ Addison never printed a follow-up, so we don’t know whether the man ever got out of the chair. I like to think he did, eventually, the day it told him to.