Animate the head:
The biped can breathe as it swims, if you animate the head rotation
appropriately.
1 In the Left viewport, select the biped's head, Bip01 Head.2 Move the time slider to frame 0 and rotate the head about 70 degrees
around the X axis, so the biped’s left ear is pointing down.Rotate the head for breathing motion.TIPWatch the Perspective viewport while rotating in the Left viewport.3 At frame 20, rotate the head back down.4 Hold down the Shift key and drag to copy the key at frame 0 to frame 40.
Watch the status area to know when you are at frame 40.Creating a Simple Freeform Animation | 789