[Jetboy2]

Without seeing you it's difficult to make an assessment, but it sounds like this:

Your head leaning forward: A sign of "upper cross syndrome", a muscular imbalance where the pectorals, trapezius and levator scapula are "tight". The deep neck flexors, rhomboids, and serratus anterior are "weak". So you want to increase flexibility (stretch) the tight areas and strengthen the weak areas.

Your butt sticking out: A sign of "lower cross syndrome", a muscular imbalance where the erector spinae and iliopsoas are "tight". The gluteus maximus and abdominals are "weak". Again, you want to increase flexibility (stretch) the tight areas and strengthen the weak areas.

** Oh, "tight" and "weak" refers to the muscular strength relative to one another, ie you may have strong rhomboids, but they're overpowered by the pecs...**

The problem is that just doing general lifts won't necessarily fix this. In fact, the postural problem can easily lead to injuries. It's likely that you need to add a flexibility component to your workouts.

What can you do about it? A chiropractor may be able to help if you can afford it and find the right chiropractor. Another source that I've found to work well for this sort of thing are the "prehab" exercises in Mark Verstegen's book, "Core Performance".

This is all very abbreviated, but hopefully useful.