Is it better form to run with your body perpendicular to the ground or with a slightly forward lean???

Not many people run perfectly perpendicular. I myself prefer the lean!

But which is better??? I can see advantages to both. Perpendicular you are putting less stress on your quads and thus saving energy, and leaning forward you are using gravity to pull you forward.

According to Lydiard you should run as straight and tall as possible, NO LEAN. Also if yo look at most world class track people they all have a very upright posture. As already stated this will save you energy but it will also open up your chest cavity and windpipe more and allow you to breath in a greater volume. If somebody finds leaning easier it is probably because they have a weak core or just do crunches and never work their back muscles so they don't have the strength to run with more efficient form for long periods. I say keep your head high, remember your a runner, not a jogger, and don't run like a soccer mom going for her first sub-5 hour marathon.

Many top runners either run vertically or leaning slightly forward. Gravity obviously doesn't "pull" you forward.

There is a book with a good comparison between the Kenyans and the trailing Mexicans in a top road race. The leaners were leading.

Run parallel to the ground. Try it, you'll like it.

Steep hills are going to be fun going up or down, eh?

The truth is, the slight forward lean isn't always obvious from photos. Sometimes it is, but not always. It's not hard to add to your own running, and it makes a difference. Simply shorten your stride a little, speed up your cadence a little, and very slightly shift your center of gravity forward by leaning slightly. Imagine that you're a 2x4 being carried upright in the palm of your own hand. How would you make the 2x4 move forward? You'd allow it to tilt very slightly and then "follow" it from down below with your cupping hand. The tilt has to be very slight, because any more than slight and the 2x4 either falls or forces your cupping hand to "sprint."

This isn't a bad analogy, actually. Try it. It's trick at first, and then you begin to get a subtle feedback loop going and it's as if the 2x4 is moving of its own accord. That's what a slight forward lean gives you.

The reason a slight forward lean is important, I think, is because a slight backward lean--rocking back very slightly on your heels--is something that many of us end up grooving into our stride from putting in LSD miles. And it's deadly. You DON'T want that. So if you're going to err, it should be in the other direction: very slight forward lean, combined with slightly shorter faster stride.

Be the 2x4!

Tom Ecker did a study of this, as have others. He would say that "true" body lean is a function of acceleration and air resistance, period, and that at a level speed the center of mass is slightly in front of the foot at the midpoint of the support phase (in practical terms, this midpoint is when the two knees are even with each other). This "slightly in front" is to offset air resistance. He would say that body lean, as a function of physics, cannot and ought not be coached.

I understand Ecker's point. Even if "lean" is determined by physics, however, it's still possible to have a "bending" (forward or backward) of the *torso*. If you look at side-on photos of top runners who are running at steady speed, you can see that the great majority (both sexes, all races) *appear* to have a bit of forward lean. I think that this would have to be the result, if one runs with a properly aligned body.

I would contend that those with completely erect carriage are actually bending the torso back a bit. This fosters a footplant well in front of the center of mass--that's a braking force in itself, but it also puts a lot of stress on the hamstrings to pull the body over the foot. Human legs are better at pushing (quads) than pulling (hamstrings), so I think most people with truly erect carriage are running less efficiently than they could be.

Brooks Johnson had much to say about body lean, and (his racial statements aside) I think he was closer to correct on this point than a lot of other coaches/runners are.

Having said that: When I occasionally encountered a student who appeared too straight-up-and-down while running, I didn't *coach* a lean as such. I would focus on abs/core work, to level the pelvis and bring the body into better alignment; and I would emphasize "keeping the feet under and behind you," which was complemented by a focus on the backward, not forward, swing of the arms. The net result tended to be a little more of a "forward lean"--which I guess, strictly speaking, was less of a backward bend. There was also typically less of an overstride.

KudzuRunner, I missed your response while typing mine. I think the two posts complement each other well.