I've been taking indoor cycling for at least 12 years and instructing classes for the last ten years. In that time I've seen cranks break at least four times. Because I instruct the members to have their hands on the handlebars at all times, unless they're taking a drink, or wiping off sweat, those cranks breaking didn't result in any injuries.

My certifications (three different ones) don't condone cycling with no hands. I don't know of any that do.

Again, it comes down to...if you don't do it outside, and if it doesn't feel right....don't do it.

It really doesn't matter whether you are in a class or not. If it's not comfortable for you, or if you feel it's incorrect for you to do, just continue pedaling and don't adhere to peer pressure.

It's instructors such as these that give indoor cycling a bad reputation.