sentences:  Besides runic divination, Flowers also advocated the "runic gymnastics" ("Runengymnastik") developed in the 1920s by Friedrich Marby, under the name of "Rune-Yoga" (also "Runic Yoga", "Stadhagaldr").In 1990, Stephan Grundy, a.k.a.Kveldulf Gundarsson, described runic magic as the active principle as opposed to passive interpretations based on runic divination.