Someone posted this on the U List so I thought I'd share in case there are some of you who stay inside in the winter months.

http://www.thepostgame.com/blog/training-day/201211/how-treadmill-killing-your-workout

Missed the mark on your last trail run? If you've been training indoors, blame your treadmill.

According to a study published in the Journal of Strength and Conditioning Research, walking or running indoors requires less effort than moving at the same speed outdoors.

Researchers tracked how much energy 14 people ages 20 to 26 burned as they walked on a treadmill compared to walking outdoors, and found that choosing a 3 percent slope on the treadmill most accurately matched the energy requirements of walking on flat terrain outdoors.

That’s because running on rough or uneven terrain outdoors takes 10 percent more energy than plodding along on your smooth treadmill, says the study’s lead researcher, Luigi Fattorini, a professor at the Sapienza University of Rome. Throw in the wind and you really need to crank up the slope: If there's a gentle breeze at 9 miles per hour, you expend 5.5 percent more energy than you would without wind.

Your move: To prepare for a race, train at an incline of 3 percent or higher -- and when possible, train in the same type of shoe you plan to race in. (Need suggestions? Check out The Best Running Shoes For Men.) Researchers in the study had people wear running shoes on the treadmill, but measured their outdoor caloric burn while they wore trekking boots. Switching up your shoes can throw off your time since shoes with greater ankle support -- like most hiking boots and many trail running shoes -- limit your ankle flex, can make you less efficient, and force you to work harder.

Let me get this straight, walking on a treadmill indoors wearing running shoes takes about 10% less energy than walking outside on a trail in trekking boots. Although the study points out some differences, I would have expected the researchers to be aware of the shoe issue and supply the "guinea pigs" with identical shoes for the test runs on the trail and the treadmill.

Still, all in all, a nice study. Thanks for sharing!

Here is my clinical judgement on treadmills (based on my own double blind experiments) - running on a piece of moving rubber...

SUCKS!!!!

I ran on a treadmill once.  I found it to be much more difficult than running outside because you have to focus on staying awake as much as or more than you have to focus on running.

In my opinion treadmills suck enough that I will run in any outdoor conditions rather than run on a treadmill.  Rain, freezing rain, sleet, snow, hail, lightning, high winds, day, night, whatever...  It is all better than enduring a treadmill run for me.  If the snow is deep enough I resort to snowshoes. If the ice is bad enough, stabilicers or screw shoes come out.

But really I came on to ask - Which hurts more - falling on a treadmill or a trail?

Although I haven't done the former, I'd say it would definitely hurt more (physically and psychologically -- imagine the stares/laughs you'd get!)  I wear my trail falling wounds proudly; doubt I'd do that with a treadmill fall.