The leg that is on the ground and is pushing the body forward. This leg stays on the ground for an entire step.
Swinging Leg
The leg that is not on the ground and is swinging forward to get ready
to catch the body as it moves forward. This leg touches the ground on the first and last frames, but is off the ground for every other frame during a step.
Leading Leg
The leg that is ahead of the body and the other foot.
Trailing Leg
The leg that is behind the body and the other foot.
Contact position
This is a pose where both feet have contact with the ground. The leading
leg is usually straight at this point, wheras the trailing leg is usually
slightly bent.
Passing Position
This is the point halfway between the first and second contact points.
This is a pose where both feet are directly underneath the body. The
body weight is only on the pushing leg which is slightly bent. The swinging
leg is bent slightly more, lifting the foot off the ground with the
toes pointing downwards. The body is slightly higher than at the contact
position.
Down position
This is the point halfway between the first contact position and
the passing position. The body is at its lowest position and the pushing
leg has just taken the entire weight of the body. The swinging leg has
it's toes still pointing downwards.
Up position
This is the point halfway between the second passing position and the final contact position. The body is at its highest because the pushing leg is straight and on its toes.
Right Leg / Left Leg (also applies to arms & feet)
Note: THIS IS FROM THE PERSPECTIVE OF YOUR CHARACTER.
For example: the right leg refers to the character's right leg. If you
character is in profile and is facing the left, then the leg furthest
from the camera is the right leg. This applies to feet, arms, and hands
as well.
