Let me just preface this by saying that I worked as a personal trainer for years and, for the most part, I steered my clients towards cardio programs that did not involve a lot of high-impact running. The bottom line is this—an effective cardio workout is all about getting your heart rate into the appropriate training zones—and you don't need to run in order to achieve this. That's where Nautilus is coming from with the Mobia.

Mobia strengthens the core, builds endurance and improves balance by combining the movements of the most popular and effective gym equipment: the forward motion of a treadmill, the stepping motion of a stair stepper and the low-impact benefits of an elliptical. This three-in-one motion is possible because Mobia operates with two separate "treadles" that rise to meet the users` feet as they walk. The action of pushing down the gently resistant treadles provides an intense workout with maximum efficiency, while reducing stress on knees and ankles.

So you are walking here—not running. But the stair-stepping and elliptical motion should provide enough of a challenge that even fit users can get a real workout. Of course, it is up to you to decide whether or not walking vs running will keep you motivated—but the $2000 price tag might decide for you. [Mobia and Reuters]

The Price: $40

The Verdict: This is one of my favorite inventions ever. Treadmill computing—or using a treadputer—is one of those ideas that's ideal for out-of-shape people who work at home, since you're still capable of doing all the work you were doing before, except now your legs are moving. Its major barrier is the fact that you had to have a treadmill, plus a stable enough platform to keep your laptop on. If you could rig that up yourself, great, but most of us were too lazy or too disinclined to. Now it just costs $40.

To answer your first question, yes, it is ill-advised to type and run at the same time. But typing and walking fast, or running and just watching something on your computer works just fine. In fact, I'm typing this entire review up while I'm walking on my treadmill.

How it works: The SurfShelf consists of two interlocking polycarbonate pieces supported by either one or two straps to your treadmill, elliptical or stationary bike. If rigged up correctly—something I had to ask for help with—it's incredibly stable, capable of supporting somewhere in the neighborhood of 55 pounds. Plenty solid enough for your laptop provided you don't constantly lean on it.

This thing has basically turned working into exercise. By spending 2-3 hours a day typing, emailing, and reviewing while walking, you basically get free calorie burn doing something you'd be doing anyway! According to Nike+, 2 hours of fast walking while working burns 1,000 calories. And even if you're not lucky enough to work from home, being able to watch YouTube or BitTorrented content makes any workout go faster.

Assuming you already own a treadmill that's gathering dust, the SurfShelf is the easiest way of getting you back on that thing. And if you're a freelancer or the type of person who spends much of your day on a computer, this could be the healthiest gadget you buy this year. [SurfShelf]

Makes treadputering an incredibly straightforward process

Relatively cheap

Stable enough that you can trust your laptop to it

Instructions aren't universal enough for every type of exercise machine, but you can get the idea fairly easily

Since there's very little gravity in space, is there an elastic strap to pull the guy down toward the treadmill to simulate gravity? Or is the guy just whirling his legs around like the Roadrunner? [Orlando Sentinel via TV Squad]

This is a funny concept in the first place, because as anyone who has played WoW know, you do a LOT of running. Miles upon virtual miles of terrain can be covered in a short session, usually at a pretty fast clip. The guys over at Manapotions.com went to great lengths to estimate the actual speed of their avatars, then built a surprisingly effective apparatus out of some old treadmills, bikes wheels and optical mice (for speed tracking). The results was kind of like the ultimate expression of the Wii "get involved in the game" ethos, except with 1000% more exertion and 97% less fun. Click through to see the build process and gameplay notes. [Mana Potions]

Why not allow people to jog through, say, the underwater city of Rapture from BioShock? Sure, a country dirt road in the summertime might be nice, but when you can put anything at all up there you might as well think outside the box. And if you can make running on a treadmill feel like a video game, maybe, just maybe you'll be able to get a whole new group of people into exercising. And that wouldn't be something even the biggest cynics could make fun of. Much. [New Launches via Ubergizmos]

Despite it's name, the JW Treadmill desk can accommodate just about any exercise machines you have in the house. It also features electronically controlled monitor height adjustment and a variety of optional laminates, bumper molding and frame colors to match your decor. Unfortunately, precisely how much one of these desks will set you back is not known, but I have no doubt that it will be expensive—especially when customized. [Treadmill Desk via Born Rich]

The best part about the technology is that the user is free to wallk, jog, or run with a full-range of motion in both the upper and lower body. And the design of the enclosure is such that the user feels very little of the force needed to hold their weight. It will probably cost a fortune, but a device like this should find a home in plenty of medical facilities and gyms (hopefully) in the near future. Naturally, the Alter-G has the potential to be an invaluable tool for injured patients and the elderly, but it would be an exceptional tool to get those who are just plain fat and out of shape up and moving. [Alter-G via MedGadget]

The Walkstation doesn't go faster than 3mph so you never move beyond a leisurely stroll. The treadmill/desk includes plenty of features that make walking and typing comfortable, including a large adjustable workspace that raises and lowers to match your height, and a soft raised wrist bar that doubles as a handrail for stability. It also has a kill switch for the treadmill controls, in case you get distracted and forget to keep walking.

The Walkstation lacks a heart rate monitor or any other health information besides the number of calories burned, making it difficult to track your progress. Maybe that'll be in v2.0.

In case you want one, it will be available to businesses in November for about $4,000, and Steelcase reps told us that they're working on a consumer edition for Spring 2008.

[Ed. note: The person you see in the video and gallery is NOT Gizmodo's rookie NYC reporter Jennifer Hooker. Just in case you were wondering.]

Sure, $4,000 is a lot of money, but it's pennies compared to remodeling your pool to fit more than two old dudes and some kids. – Jason Chen

Product Page [Hammacher via Red Ferret via Geekologie]

Who's paying these people? Seriously, are you surprised that obese people lost weight when forced to walk 8 hours a day, 5 days a week rather than sit down? I mean, I'd probably get sweet biceps if you attached a laptop to some weights, but it doesn't mean I'd want to subject myself to that kind of exertion all day every day. Go cure cancer or something, you idiots. –Adam Frucci

Making work even more of a slog takes weight off [Reuters]

Product Page [via Ubergizmo]