Cold water will be good to thaw as one should allow some time to defrost. Rapid change in temperature may spoil the meat, hence warm water is not advisable to thaw.
Cold water is the preferred method to thaw if there is not enough time to thaw in the refrigerator. If food is brought up to a temperature that bacteria can begin to grow, then food will be spoiled and inedible.
Hot water will thaw meat faster but cold water is a little better to use. The hot or warm water can tear microscopic fibers and make the meat taste different once it is cooked.
