Hmmm,
Mondo, it sounds to me as though you are doing smaller weights, more repetitions. This is great if you are trying to lose weight, ie the show "the biggest loser".
What you need to do is use more weight, less repetitions. I could be wrong, your trainer might be giving you lesser weights for a reason.
3 sets of 10 rep's, maximum weight.
What I like to do is use the maximum weight on the last set, I may not get to 10 rep's, maybe only do 6 to 8 rep's. To mix it up, I use maximum weight on the 2nd set, once again I may not do 10 rep's, but for the 3rd set, go down a weight and do the 10 rep's.
Tell your trainer, that you are not happy, you want muscle and you want shape, if your trainer does not want you to change or won't tell you why he is doing your workout this way, then dump him!
Just because they are a personal trainer, does not make them right!
Watch some of the videos on You Tube under body building, and see what they are doing. Heavy weights!
MightyTriby