Which is more effective in tightening the thigh and hip area. Treadmill, elliptical, stationary bike or possibly something totally different.

I like my recumbent bike.

Excuse me what is that?

Recumbent bike is the one where you sit down with legs in front of you instead of under you. My former gym had an Arc trainer (by Cybex) that was awesome for that area. Something like a stairclimber would work or you can do lunges & squats. They suck but really help.

I can feel the muscles working all the way into my core....with the bike....and its easy on the knees.