I have attended Les Mills Body Pump at a NYC gym, and at fitness conventions. The classes I have seen have paid little or no attention to correct lifting and alignment. (granted it has been at least 2 years since I have taken one). The instructors gave lip service to alignment, but I saw terrible form, (including the instructors), and never saw a correction.
My other problem with the class is it is too hard to challenge the legs (at least for advanced participants),while working upper body. For example, I can handle 20 pounds while doing a front raise, but don’t feel that is enough intensity for me to squat with.
I do believe the classes could be a positive introduction to weight training, but feel more emphasis must be paid to instructor training, and that class sizes should be limited so corrections can be made.
I am Body Pump certified and teach it a couple times a week for 6 years. The training is held over a weekend. You are not certified after the training! You must learn the 60 mins of choreographed material. You must then present the entire class to a live audieance while being video taped. The tape is submitted the Les Mills co. for assessment. They will determine if you are ready to teach or if you need more time, in which case you will need to resubmit a video.
I hope that helps. If you would like to chat about it my email is below.