The treadmill desk I bought was this one:
But before talking specifically about why, I'd like to talk about some of the other options available and why I didn't get them. I'm going to list them by the key reason I didn't choose a particular desk, though multiple reasons often applied.
Pretty much every ready-made solution out there could fall into this category, even the LifeSpan. But there are some that are absolutely egregious.
Steelcase has 2 different models, depending on what you want. The Walkstation is strictly for standing/walking, while the awkwardly-named Sit-to-Walkstation is wide enough that you can put a chair next to the treadmill and use it for times when you don't want to stand or walk. These things start at $4400, with the bigger one adding another $400. And that's just for the desk and the treadmill. Their pictures show numerous accessories which can add hundreds, if not thousands, more. Now don't get me wrong; I absolutely want one of these. They are great looking desks, I expect them to be sturdy, and I love the back panel and accessory system. But this is simply too much money, particularly for my first treadmill desk. If I manage to stick with it for a year or two, I will definitely consider upgrading. It is just too much money to risk at this point.
The Signature 9000 desk at ~$2500 is 1/2 the price of the Steelcases, so could be viewed in that light as a bargain. I really didn't want to go over $1000, and I definitely didn't want to go over $2000. Bargain though it may be, it was still too pricey. Another strike against them is that I'm too heavy for their entry-level treadmill, so I would have needed to get the upgraded treadmill, which was another $600 or so.
It is possible to buy a treadmill without all of the vertical gadgetry that an average model in a fitness facility would have. I don't need big fancy arms or a giant display as these would most likely not be viewable anyway due to the desk, and would probably limit my desk choices. So if you can find a desk that you like, you don't necessarily have to find some place that sells desk+treadmill combinations. You can buy a treadmill base, usually with a detached control panel, such as the The Tread by TreadDesk. It is $820, but then you need to add another $100+ in shipping, so it isn't cheap. But if you can find or already have a cheap desk, then this is one way to save some money. I did find a competing model, but it was basically the same price.
I mention these only as didn't-buys, not wouldn't-buys. If I hadn't found the LifeSpan, I most likely would have purchased The Tread and one of the desks mentioned below.
I'm a big IKEA fan, and one desk that routinely turns up in standing/walking desk searches is the FREDRIK. This is advertised as an adjustable-height desk, and while I suppose that's technically true, it looked to me like you'd have to semi-dismantle it in order to reconfigure. This is $150 dollars, so not horribly expensive at all, and there is a narrower version that is even less expensive. I would need to raise the primary desk surface higher than they suggest, but I found numerous examples of people having done exactly that without any problems.
We took a trip to our nearest IKEA to check it out, fully intending to buy that very night. They had a couple of floor models set up that I could kick the tires on, and in general I felt that it allowed entirely too much motion. It was quite a bit wobbly, and since I would set my monitor on the highest shelf, that motion would only be amplified. I was trying to decide if there was any way I could brace it to reduce motion, but the legs are metal. If they were wood, I'd probably bolt a couple of braces to it, but I didn't think there was much I could do with metal, and I didn't really want to risk it. I was a bit disappointed, since this was certainly the least expensive option that I had found, but in my opinion it wasn't sturdy enough. That said, there are numerous examples of people using these just fine, so your mileage may vary.
One thing I found frustrating while looking for adjustable-height desks is that they frequently don't account for a tall person standing on a treadmill. I would be on the upper-end of the available height range as-is, but when you add 4-6 inches of treadmill, I'm beyond the maximum height by several inches. Could I make them work? Possibly. But I don't see the point in spending lots of money on something that I can already assume isn't suitable. I don't feel like trying to put the desk up on blocks, or buying additional risers just to get the keyboard up to a decent height. As I type this, my desk is 52 1/2 inches high. It might be a little high, so I have room to go down if I need to. But I also have several more inches I could go up. When most of the desks I found topped out under 50", I was very nervous that they would be too short.
A popular choice, naturally, is the GeekDesk. The smaller model has a maximum height of 48". The larger model (+$200) goes another inch. Each still under 50", and though they come highly recommended, still just short enough that I don't want to risk that they are too short. After I spend some time with the LifeSpan, and possibly make some height adjustments, I might find that 49" is sufficient. But until I know that for a fact, I'm going to choose a desk that has a height range that should easily be accommodating.
There are numerous other desk models in this genre that largely have the same limitation. If you're tall (and I'm not a giant, at 6'1") and will be on a treadmill, chances are that the majority of standing desks will be too short. I've been reading about standing/walking at your desk for a good 8 or 9 months now, and in that time I would say that the concept is increasing in popularity. If I'm correct about that, then I suspect that the standing desk manufacturers will gradually start upgrading their products to add a few more inches of height. In my case, GeekDesk probably lost a sale, as the combination of GeekDesk+The Tread was cheaper than the Signature 9000. But the likelihood of the GeekDesk being too short made it a non-starter for me.
This is basically a sub-set of "Too Expensive". The vast majority of adjustable-height desks have powered height adjustment. While this is convenient, it also adds significant cost to the desk. You can find non-adjustable standing desks, in some cases as low as a couple hundred bucks. The GeekDesk might have been the least-expensive powered height one I saw at about $750 + S&H. That's a lot of money for what is otherwise a very spartan desk. The regular desk I've been using for years has a hutch, file drawers, a compartment for a tower computer, etc. Most powered desks have none of these things. They have relatively basic desktops, those desktops move up and down, and that's about it. So you're paying hundreds, possibly thousands, of dollars for the ability to adjust the height of your desk with the touch of a button.
That's all fine and good, but how often are you really going to adjust the height of the desk? If your intention is to both walk and sit, then you will be adjusting the height a lot, so I can see splurging on the mechanicals to do so easily. But if your intention is solely to stand or to walk, then chances are there won't be much adjusting at all. You'll have to get it dialed in at first, so let's say you futz with it a few times during the first month or so. After that, how often would you change height? Once a year? Ever again? Either way, you've now paid significant money for a motor that sits unused 99.999% of the time. Unless you know in advance the specific height that you need - in which case you could buy a fixed-height desk and probably save lots of money - then you absolutely do want an adjustable-height desk so that you can find your appropriate height. But are you really going to change the height so often that the ability to do so needs to be powered? Probably not.
All of that leads me to why I chose the LifeSpan.
- Sufficient height range. They claim that 6'8" people can use this desk. That's more than enough for me on a treadmill. Their advertised maximum height is 52", though I just realized I'm currently using it a little above that very height, and still have 3 more clicks available, so I think they are being conservative.
- Reasonable price, mostly. At $1300 (and it was shipped free from Amazon), it is roughly 1/4 the price of the Steelcase, and about 1/2 the Signature. It was also cheaper than pretty much every other combination of standing desk + treadmill that I looked at. About the only way I could have gone cheaper (with new stuff, I mean) is if the Fredrik desk had been sturdy, and even that would have only saved another $100 or so. It still feels like a big chunk of money, and if they could get this down to $999 or so they'd have a solid winner on their hands, but as-is I consider the price to be reasonable.
- Manual height adjustment, although I can't say I specifically sought that out as a feature. Would I like powered adjustment? Absolutely. Would I like to add another $500 or more to the price of this desk? No, thank you.
- Positive reviews across the board on Amazon.
If you are the DIY type, you can save yourself boatloads of money over what I've done here. I didn't care to invest the time that would be required to do so, and I've never built anything that I'd feel comfortable putting my computer on. Bottom line is that this desk supports my livelihood, now physically as well as financially, and I want it to be a good product. That's worth a couple of bucks to me.
And let's face it, I'm taking a risk here. I already had a bad experience with standing at my desk, but at least that experiment didn't cost me a dime. So this is a new experiment, and if it is ultimately doomed to fail, I'd like to minimize my cash outlay in the process. But if having nicer (-than DIY) equipment ultimately contributes to the success of this project, then that will be money well spent. After considering many options and scenarios, I decided that the LifeSpan fell nicely into the sweet spot between risk and reward.
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