Body Talk is a track that was released with the quest Elemental Workshop III.
Body Talk is a synonym for Body Language, such as gestures, etc. Since Elemental Workshop III is mainly about making Body Elemental items, it would make sense to have a track named such as it is. Many of RuneScape's music tracks are named in similar ways to this one.
There is also a song, composted by the glam metal band Ratt, which is called "Body talk".