Muscle worship (also called sthenolagnia) is a form of body worship in which one participant, the worshiper, touches the muscles of another participant, the dominant, in a sexually arousing manner. The practice of muscle worship can involve various wrestling holds and lifts, as well as the rubbing, massaging, kissing, or licking of a dominant's body. Although muscle worship participants may be of any gender or sexual orientation, the dominant (often a professional bodybuilder, fitness competitor, or wrestler), is almost always an individual with either a large body size or a high degree of visible muscle mass, while the worshiper is often, but not always, skinnier or smaller.
The Encyclopedia of Unusual Sex Practices lists ("sexual arousal from displaying strength or muscles") and ("arousal from strength") as paraphilias associated with the practice of wrestling for erotic purpose, although there have been no studies concerning them. Forensic and Medico-Legal Aspects of Sexual Crimes and Unusual Sexual Practices, the 2008 comprehensive monograph of Anil Aggrawal, only defines the two terms, and does not provide any additional information.
As with many BDSM-related practices, the amount of force and pain involved depends on the desires of the participants. While some dominants might use their size and strength to pin a smaller worshiper, thereby forcing that worshiper to come in contact with the dominant's muscles, others might only display their muscles and allow a worshiper to touch them. People who participate in muscle worship generally find the practice sexually arousing, but some male bodybuilders offer muscle worship sessions only for monetary gain, as bodybuilding does not always guarantee a steady income. For well-known competitors, this can also draw in fans who want a chance to meet with and touch the muscles of bodybuilders whom they idolize.