Top shelf (Playboy centerfold) research

In the last decade or so, researchers investigating human preferences for male and female body shapes have turned to a previously under-explored academic resource – in the form of double-page gatefolded magazine spreads. Specifically, the centerfolds of so-called ‘top-shelf’ publications.
For example, researchers at the School of Kinesiology and Health Science, York University, North York, Ontario, Canada have examined – Thinness and body shape of Playboy centerfolds from 1978 to 1998. (Int J Obes Relat Metab Disord. 2001 Apr;25(4):590-2.)

Whilst the Department of Psychology, American University, Washington, The Biological Psychiatry Laboratory, McLean Hospital, Belmont, Massachusetts and the Department of Psychiatry, Harvard Medical School, Boston, Massachusetts looked at – Cultural Expectations of Muscularity in Men: The Evolution of Playgirl Centerfolds (Int J Eat Disord 29: 90–93, 2001)