A-skip rhythm with a little extra snap for fast feet.
Stay tall and bouncy, drive the knee up and strike down right under your body.
AC-Skips take the standard A-skip rhythm and sharpen the downstroke, the foot snaps back to the ground faster, which cranks up the demand on the calves to absorb and rebound off each contact. Everything happens on the balls of the feet, so ankle stiffness and ground-contact speed are the qualities being trained. They earn their place in speed warm-ups when plain A-skips have become comfortable and you want more snap per contact.
AC-skips keep the same knee-up skip pattern but emphasise a faster, crisper snap of the foot back to the ground. Think of them as A-skips with the tempo dial turned up on the downstroke.
Late in the warm-up, after easier drills like plain skipping and A-skips have primed your calves. They sit one notch below actual sprinting in intensity, so they slot in just before your fast running.
That is fine, forward travel is modest by design. The drill is about vertical rhythm and striking down under your hips, if you reach out in front to cover ground, you are practising overstriding.
