Question roughly lifting weights?

okay i have hear both sides about this subject, so i'm looking for more opinion:
is it better to do a short amount of repetitions with pouring weights?
OR
is it better to do a long amount of repetitions with lighter weights? Depends on what you want to accomplish, basically. Heavy weights, low reps tends to build mass while buoyant weights, high reps builds serenity. Also, if you have any reciprocated problems, it's best to start with lighting weights to prevent further damage to your joint.