Okay, I ask you, can someone tell me WHY you use a spinner for squatting? Wouldn't it make sense to stand on the floor?!
LOL! That IS the question......... I have no idea. Wouldn't it make sense to NOT do squats in Spinning at all? Just ride and do other exercises elsewhere?

As for the "stand and grind" routine, if the instructor is following Spin guidlines, cadence for a hill is supposed to be between 60-80 rpm, no slower. That's not quite a grind but is a cadence that can be used while climbing actual hills outside and should be safe on knees.

Flat riding should be done at 80-110 rpm, again according to Johnny G. Any faster and the flywheel on the bike is doing too much of the work. So sometime when you are in spin class, check your cadence and see how you're doing. I try to have a cadence check at least twice per class, especially if there are new riders in the class, too help everyone get a feel as to where they're at.

Sprinting.......... We have one instructor who simply encourages riders "faster, faster!" when we sprint. His legs are a blur on the bike, but his resistance is so low that there is not much work involved. Before beginning a sprint, resistance needs to be added, more speed isn't always necessary, just intense, maximum effort for the length of the sprint (never longer than 30 seconds.) It's much more challenging this way than simply whipping legs around at 150+ rpm as the wheels zips along. (My pet peeve in spin, so please excuse the ramble here.)

Jumping......... it's interesting to read all the different opinions on that. I have to agree that it doesn't seem to have much to do with riding. Some people like it, some don't. I try to use it sparingly, once, rarely twice, per class, and sometimes not at all.

Running.......... I actually like this even tho' I certainly don't do it often when I am outdoors. If you concentrate on keeping your weight over the pedals, NOT on your hands and arms, keeping a relatively still upper body, I think it is a good workout for your quads and also gives you a sense of floating on the pedals (think of Lance climbing Mount Ventoux) if you can keep an even pressure on those pedals for the entire stroke. It forces you to really concentrate on form. ::::::shrugging:::::::: Each to their own.

I say, try to enjoy the classes. At least you are with other people. If you just don't like what the class is doing, be smart and do your own thing! It's your ride! You are probably paying to be there, make it work for you.