In the swing phase, what is the state of the reference limb?

During the swing phase of gait, the reference limb is indeed not in contact with the ground. This phase occurs after the foot has pushed off and is moving forward to prepare for the next step. The swing phase is essential for forward progression, allowing the leg to clear the ground and reposition for the heel strike of the subsequent gait cycle. It is characterized by the leg moving in the air, free from contact with the ground, optimizing stride length and minimizing any potential hazards that could lead to tripping or falling. This phase represents a critical component of normal walking mechanics, emphasizing the importance of limb mobility and coordination.