At 39, Giggs has now won an incredible 13 league titles following Monday night's championship-clinching 3-0 win over Aston Villa at Old Trafford.
Carrick said: "I keep talking about him but what else is there left to say?"
He added: "It is sensational that he is still able to do that after all this time. It is not just physical, it is mental, having the drive and desire to do it every day. The league wasn't won tonight, it was won all season with all the work we have put in.
"Ryan is out there training every day. The standard he has set is unbelievable. He is a legend. It is a throwaway comment too often. But he is the legend really. It is a pleasure to play with him and work with him every day."