Matlab bin Abdullah says that once there was a difference of opinion among some people regarding recitation in the Zuhr and Asr prayers, so they sent a man to Kharijah bin Zaid (may Allah have mercy on him) to ask about this issue. He narrated from his father that the Prophet Muhammad (peace and blessings be upon him) used to stand for a long time and would keep moving his lips. I think this could only be because of recitation, so I also recite (in these prayers).