Simulating outdoor running strength on a treadmill

November 19, 2008 6:35 AM

On a treadmill, what kind of slope/incline% should I set to simulate the strength needed for normal outdoor running?

I like to run on a treadmill in my gym. However, I have learned that the force needed to run on a treadmill is lower than normal running, because the floor moves for you (i.e. you jump up and down, but don't pull yourself forward).

A way to increase the force needed is to set a slope / incline on the treadmill, i.e. simulating running slightly uphill.

My question: What is a good percentage slope to simulate the strength needed in normal, outdoor, horizontal running?

posted by lord_yo to sports, hobbies, & recreation (8 comments total)

This is totally subjective, but I always found that about a 2-3% incline seemed to get me to the same level of exertion that running outside (roads, not on a track) did.

However I think this may just be that the areas I was running in had gentle grades. I'm not sure that your assumption -- "the force needed to run on a treadmill is lower than normal running, because the floor moves for you" -- is really correct.

I don't want to turn this into an airplane-on-a-conveyor-belt thing, but I think that running on a belt that's moving backwards is essentially the same as running forwards at the speed that the belt is moving backwards. You really are running. The only force you're not subject to is air/wind resistance (which can be significant on a blustery day).
posted by Kadin2048 at 7:01 AM on November 19, 2008

Are you sure that your premise is correct? If I jump straight up and down on a treadmill, I'm pretty sure I'll fall off the ass-end of it with a quickness...so I think I do pull myself forward.

Anyway, the biomechanics of running uphill and running laterally are different. You take shorter steps going uphill, for one thing, and I'm pretty sure you use your quads a lot more and your hamstrings less. If running on a treadmill truly is easier, than I would compensate by running faster.
posted by creasy boy at 7:06 AM on November 19, 2008

This study says 1%, but I've always found 3% more closely simulates the feeling I get when I run outside. But then I find running outside to be more difficult than a treadmill, so YMMV.
posted by longdaysjourney at 7:23 AM on November 19, 2008

This chart might be helpful too!
posted by longdaysjourney at 7:25 AM on November 19, 2008

It has always seemed to me like running on a treadmill is easier because it's such a guaranteed smooth, level surface. Outside, I have to pick my feet up higher to avoid tripping on sidewalk cracks, sticks, whatever, but on the treadmill I can basically shuffle along with my feet barely above the surface. If I pay attention to not letting my gait get lazy like that, the treadmill workout gets more difficult.
posted by vytae at 7:33 AM on November 19, 2008

I've heard that a 1% incline on a treadmill simulates running outside on a flat surface, and Googling for "treadmill incline outdoor" gets mostly that number. This page suggests, however, that there is no significant difference between a 0% incline and track running, but then again a track may not be equivalent to your favorite running path.

Anecdotally speaking, I run much faster on a treadmill with 0-0.5% incline than I do outside, but there are a whole ton of factors that muddy things up (I run with a partner outside, I listen to music on the treadmill only, I'm more aware of my speed on the treadmill, I often run farther outside, etc).
posted by Metroid Baby at 7:34 AM on November 19, 2008

Many roads/paths have false flats meaning they look like level surfaces but really have inclines. I'd go with the 1% incline.

I trained on mostly flat surfaces for a race that had hills. Huge mistake.
posted by collocation at 7:39 AM on November 19, 2008

Ooh, many answers - thank you!

Right, my assumption about the floor moving for me might not be correct (the conveyor belt and plane thing clearly confuses me). However, I'm sure that other factors lead to higher energy consumption outside than on a treadmill, be that wind resistance, floor consistency, hidden inclines outside, etc.

The general consenus seems to be in the 0.5 - 3% area - I've used 5% in the past, and I thought that's too much.
posted by lord_yo at 8:51 AM on November 19, 2008