Sophia is the cyclist. I didn't actually watch the episode, but I was intrigued by all your discussions so I started poking around online.
She's also a spin instructor! I've never followed the show religiously, but it seems like contestants have tended toward the more sedentary side, so I'm guessing she would have less trouble than most with the physical demands--maybe her major issues are dietary in nature?
'09 Jamis Satellite Femme | stock Jamis Road Sport -- road
'08 Trek 7.2FX | Terry Cite -- commuter
'77 Raleigh Grand Prix mixte | stock Brooks (vinyl) -- just for fun!