Well right now I am trying to lose weight and I want to keep my muscle. I am 18,, 5'4, 150 pounds right now and I have been doing cardio for a week now. I am eating 1400 calories 2 days and 1500 the rest.
How many days a week should I do body pump class to maintain muscle mass while losing weight?
All depends on the # of calories you are burning.
That being said you *should* be eating more than 1,500 calories a day.
Agreed - seems likely that you should be eating more at your age, weight and height.
Also, in response to your question - I'm not sure that Body Pump classes will have much/any impact on retaining lean body mass. Having done (and thoroughly enjoyed) many a Body Pump class, I get the impression that you are building up a combination of muscular endurance and cardiovascular fitness, neither of which are especially helpful in retaining muscle mass. This is simply because in order to be able to complete the number of reps the class demands you are lifting a weight that is much too small a percentage of your maximum to preserve muscle.
I'm sure someone more knowledgeable will correct me if I'm wrong but if you are aiming to retain muscle mass whilst losing fat (a very good aim!) then a structured heavy weight-lifting routine would be much effective.
I was reading about pump the other day and they said ideally you should do 2 - 3 classes per week with a days break in between classes to let your muscles have down time and heal. I do body pump classes and I like what they effect they are having on my body shape - I dont do any other weight training - I do cardio five times a week tho'. You do have to push yourself and add a bit more weight rather than just doing the same old weights all the time.