Some muscle rubs bring blood to the skin (some through irritation) making the skin (and as a result muscle) feel warm even though there is no change in blood flow through or temp in the muscle.
I have used insulating/water repleant substances when racing in the wet and cold. When doing a stage race in ireland where it rained non stop for 8 days, a coating of vasaline over the legs was much warmer and comfortable than any of the cycling clothes we had available.