Nothing to do with one another if the question is in a Christian Context. Prayer is prayer and smoking is smoking. One could eat, walk, fish, smoke, whatever, but there is no where in the Bible where praying is conflated with any other activity. The Lord's Supper/Communion is an act, not a prayer. An act of remberance. Paul said to pray continiously so it would seem that you could/would pray while doing most anything. But prayer is separate and distinct from the most anything