You mean BodyPump - the prechoreographed barbell resistance class?
I teach that, but I really am not a fan of it at all & wouldn't recommend that anyone do it. The only thing I think that's good about it is that it's better than NOTHING! It is at least *some* resistance training - which most women wouldn't do otherwise.
High reps typically means 15-30 or so. In BodyPump you will do, literally, 60-100 reps in about 5 minutes. Um, that's kinda nuts. I have counted up the reps & will be more than happy to scan & post copies of the choreography sheets.
Pump is such light resistance training that it's sort cardio in a bizarre way.
I think that if you're doing REAL lifting with heavy weights & want to do some light days, do 15-20 or even 30 reps, but Pump can lead to joint problems for some. I'd be interested to hear others opinions on 60-100 reps for a "light day", but I think only go if you are REALLY lacking motivation to do light weights on your own.