To fully understand the rationale behind this cartoon, you must know that scrawny, pot-smoking, lite-rock wastrel Glenn Frey reinvented himself (in a sense) with a series of ads for Bally Fitness (like this one) in the late '80s.
This cartoon is honestly not intended to be sacrilegious, but a comment on the superficiality of health club culture and the dubious prestige of celebrity spokespeople.
You kids with your PhotoShop and your fancy gadgets won't be impressed, but this bit of nonsense was made solely with MS Paint way, way, waaaayyyy back in 1996 or so.