Two papers in this issue of MPPA examine energy expenditure while playing a wind instrument and dancing. Measurement of the amount of energy required to play an instrument, dance, or sing has been done in the past, but these two papers advance our understanding of how performing artists carry out their professional activities. Since most of us don’t think about our daily lives in terms of METs or kilojoules, I will first review some basic information about human energy intake and expenditure before examining how energy expenditure studies can expand our knowledge base.