virya, potency, is retained. This accumulates until it culminates in physical and spiritual power… ojas is a subtle vital energy or substance that forms the essence of all the seven bodily tissues… It is the essential ingredient in vigor and potency, both physical and spiritual.
In the Patanjali commentary tradition, potency (virya) is a conservable vital substance whose accumulation through celibacy generates both somatic and spiritual power.
, The Yoga Sutras of Patanjali: A New Edition, Translation, and Commentary, 2009thesis