knee and lower back pains

I am taking my first spin class this quarter and every time have experienced a pain on the inside back of my left knee. I don't feel it while I'm pedaling, but can barely straighten it and hardly walk without limping when I get off the bike. Stretching helps some, but not completely. Also, since the last class I noticed some lower back pain. Could this be caused by spinning?

I have tried adjusting my seat further back. I asked someone to check if my knees were properly aligned at 3 and 9 o'clock and they supposedly were. I talked to my teacher about it and he apparently doesn't care and just told me to get someone else to check it again. Please help! I can't drop the class it's for my degree, but I don't want to ruin my knee!

Wow...I'm amazed that the instructor refuses to help you! That's just wrong. If you're getting pain in the back of your knee, I think that generally indicates that your seat may be too high. You said you tried adjusting your seat further back...perhaps that position stretched you out too much, thus resulting in the lower back pain. Try moving the seat forward a bit, and see how that feels. You might also have to raise or lower the handlebars to see what works best for you. I happen to prefer my bars being a touch lower than my seat...but I see lots of folks in the spin class that I take, with their handlebars raised up really high. I imagine the higher the bar, the more upright you will be...which might ease your back pain. I would continue to seek out the help of other experience spinners in your class, until you get your riding position dialed in.

Someone else in class told me the same thing yesterday, and wow what a difference that made! Lowering my seat really made a difference. Thank you so much for you help! =)