Walk Cycle Side view

Animating a Walk Cycle from Side view :

Key frames for a walk cycle

  

The Key Frames :

                                          To animate a walking cycle, you need three key frames (1, 2 and 3 in the list above), and one breakdown position ( 4 ) the passing position.

Most walking cycles work best at 9 frames per step = 18 frame cycle for both feet.
The animation presented here below is slower - this is a 24 frames walkcycle (for both legs) at 24 fps:

Faster than 18 frames is starting to be a run.