Armchair Cavers

Armchair Caving; n., the act of retaining membership of (or hanging around with) a caving group, whilst not participating in any actual caving-related activities.
-derivatives: Armchair Caver; one who participates in Armchair Caving.
Classic symptoms include talking about all the caves he/she has been through as if he/she knows them inside out, while in fact he/she has merely seen the entrance and headed off for a fry instead. Also known to be caused by chronic faffing. (see also – Faffing)
(from: WorldArmchair Cavers)

Armchair caver: One who talks about caving more than going underground. Modern version is the 'virtual' caver. (from: Caving Definitions)

Armchair caver: An experienced caver who now rarely if ever goes caving, but offers advice to those that do. (from: WorldSCMC - Armchair Caving Option)

As you can see, armchair caver is a well-known subtype of caver. However, the term seems to be in use mostly in Britain. I could not find a similar term in any other language including other English dialects, although it is quite easily understood in most languages.