60s pop diva, Sandy Shaw always sang barefoot, which was rather a novelty but now scientists believe singing barefoot might be better than singing in high heels. Researchers have been busy trying to understand the effects of shoe heel height on female singers' vocal production. Previous findings in non-singer show wearing heels can affect body alignment and head position. Other studies in orthodontics, sleep apnoea, and voice science suggest that head and neck positioning can alter the vocal tract.
In a paper about to be published in Voice, researchers describe a study of 30 soloists and the effects of heel height (barefoot, 10.16-cm stilettos) on three angles of singer head position (calculated from C7-tragus-nasion), during alternating periods of silence and singing.
Results indicated that all participants (100%) significantly decreased head position angle measurements (inferior and posterior head and neck movement) when singing in high heels compared with singing barefoot. Participants, on average, significantly increased head position angle measurements (superior and anterior head and neck movement) when singing compared with standing silently, and did so to a greater degree when transitioning from silent heels to singing heels compared with transitioning from silent barefoot to singing barefoot. Long-term average spectra data indicated significant spectral energy differences between barefoot and high heel singing conditions across participants. Most participants (n= 21, 70.00%) indicated they felt comfortable and sang their best while barefoot.
Rollings AA (2017) The Effects of Heel Height on Head Position, Long-Term Average Spectra, and Perceptions of Female Singers J Voice. pii: S0892-1997(17)30056-5.