This year I’ve made a serious effort to improve my physical fitness. I started lifting weights in August, and worked hard to commute to work as much as I could by bicycle (6.7 miles each way) or ski (4.1 miles). I commuted on 102 days this year, which is 40% of the possible work days in the year. I also spent a lot of time out on the trails with our now 15-year old dog, Nika. In May, I set up a standing desk at work, and as I’ll demonstrate below, this is a significant improvement over spending all those hours sitting, at least for energy consumption. As a result of all this, I feel like I am in the best shape of my life, and that makes me feel good as I enter middle age.
Here’s the summary of what I did this year (details on the calculations appear below):
The other thing I did was start standing up at my desk at work. I spent 1,258 hours at my desk after I started standing. According to the Compendium of Physical Activities, standing at work consumes 2.3 metabolic equivalent units (MET). This is the ratio of work metabolic rate over resting metabolic rate, which would be 1.0 MET. Thus, standing uses an additional 1.3 MET over resting. Sitting at a desk is 1.5 MET, which means standing adds 0.8 MET.
To use these numbers, you need an estimate of your resting metabolic rate. Using the Mifflin et al. equation on this page I get 1,691 Kcal/day, or 70.5 Kcal per hour for my height, weight, and age. For those 1,258 hours standing at work I burned an additional 71 thousand calories: 1,258 • 0.8 • 70.5 = 70,951 Kcal (the “calories” reported on food labels are technically kilocalories (Kcal) in energy units). That’s a lot of energy, just by standing instead of sitting.
The energy values in the table above were also calculated using the same methods. I fiddled with the tabular values from the compendium and got the following approximations:
- Running MET = 1.653 • speed (mph)
- Skiing = ((speed - 2.5) / 2) + 7
- Bicycling = speed - 5
- Hiking = 6
- Skating = 5.5
- Lifting = 6
Despite the amount of energy consumed by standing instead of sitting at work, I think there is a real benefit to the more intense exercises listed in the table. These strengthen and build skeletal and cardiovascular muscle in ways that simply standing all day don’t.
When all the numbers are totaled, I burned an extra 512 calories (318 exercising, 194 standing) each day in 2011. That’s certainly worth a beer or two, and I look and feel better for it even drinking them!
Last Thursday afternoon, I set up a laptop on the side of my desk, at a height reasonably comfortable for working while standing (see the photo on the right). Over the past couple years I’ve seen several articles on the Internet advocating standind desks as a way to keep a person awake and alert throughout the day. Two weeks ago there was a story in the New York Times Magazine entitled Is Sitting a Lethal Activity?, and the Internets (and NPR on Monday) have been all over the story. The punchline from the Times Magazine story:
Sitting, it would seem, is an independent pathology. Being sedentary for nine hours a day at the office is bad for your health whether you go home and watch television afterward or hit the gym. It is bad whether you are morbidly obese or marathon-runner thin. “Excessive sitting,” Dr. Levine says, “is a lethal activity.”
Last Friday was my first full day at my temporary standing desk. I worked from 6:30 until around 12:30 primarily standing (I’d say around 80 - 90% of the time), and after that I started sitting around half the time because my feet and lower back started to hurt.
Day number two was similar to the first day: after about six hours on my feet, my heels and lower back started hurting. I continued standing until I’d been on my feet for a full eight hours and then spent an hour or so sitting. My neck, shoulders, and right wrist were a little tired at the end of the day, but I think all of this has more to do with using a laptop than standing. The screen is at arm level, so I’m looking down on it all day, and because it’s smaller than my normal monitor, I think there is a bit more hunching to get close. I don’t have my usual trackball either, which probably contributes to the wrist discomfort.
The third day (Tuesday) was rough. I stood the entire day, and migrated off the laptop setup to using my regular computer (v0.2). I also rode my bicycle to work, so my legs were already tired. I made it through the first four hours without any issues, but my back started hurting about then, and by the end of the day the heels of my feet were really killing me. Part of the issue may be that I was in my slippers, and standing on the anti-static mat rather than the carpet because of the new setup. Hopefully shoes with some padding, and possibly an anti-fatigue mat will lessen the pain on my feet.
On day four I wore running shoes and removed the anti-static mat so I was standing directly on the carpet (over concrete). Both of these things helped, but again, between four and six hours into the day, my lower back started to hurt, as did the heels of my feet. But it really didn’t seem as bad as Tuesday, so I may be getting used to it. The new setup with the monitor at an appropriate height, plus a real keyboard and trackball also helps.
Thursday I woke up with a stiff neck and rode my bike to work, so I expected that standing all day would be pretty brutal, but it really is getting easier. The heels of my feet are still a little tired for the last couple hours of work, and my lower back hasn’t quite gotten used to the additional load, but it’s not affecting my concentration like it was in the beginning and I’m starting to be pretty comfortable working at the computer in this position.
Update: It’s now been a couple weeks since I started this experiment. The heels of my feet still hurt a little after a full day of work, and I occasionally experience some lower back pain during the day, but I can feel the benefits already. I’m less tired outside of work, I feel like I’m more productive at work because I am always moving around, and I don’t doubt that the setup will provide long term health benefits over sitting at work and at home for most of my waking hours. The other thing I’ve noticed is that my posture is much better in a standing position and that’s helping to relieve some of the neck stiffness I’d been living with for the past several years. It seems much easier to keep good posture while standing, than having to think about sitting up while in a chair.
All that’s really left to do is make the setup more permanent by building something to set things at the right height and getting an anti-fatigue mat for the floor in front of my keyboard.