Starting over again at the gym

My body was beginning to complain a few months before I found out that I was pregnant, and I had been thinking bout going back to the gym for a while when I signed up - the day before I found out! Having been physically active most of my life (ex dancer/dance teacher) and having stayed reasonably fit through walking, I decided to go ahead and start weight training again very carefully. My upper body needs strengthening if I want to avoid back aches from carrying the baby.

I felt absolutely wonderful after the first session!

Unfortunately, the gym instructor didn't know much about weight training during pregnancy (!) but I did some research online and found the following (http://www.fitpregnancy.com/yourpregnancy/labor_delivery/40723272.html?page=2:

The Right Weight Routine

Strength training is safe and one of the best ways to minimize aches and pains. Weight machines are ideal, especially for gym newbies, because they control your range of motion. "During pregnancy, your joints get looser, and it's easy to move outside of your normal range," says Jeffreys. However, if you're accustomed to doing free-weight exercises, you can continue.

Steer clear of any machine with a pad that presses against your belly, such as the seated row machine or abdominal machines. In addition, forgo any overhead lift, since this kind of motion can increase the curve in your lower spine (aka hyperlordosis).

The strength routine below targets the muscles that are key to reducing discomfort during pregnancy. Do 1 or 2 sets of 8 to 12 reps for each except the Plank. Choose a weight that allows you to perform the repetitions properly and comfortably. And after the first trimester, avoid any exercise done while lying on your back.

Upper/Middle Back
Best Machines: Seated cable row, lat pulldown
Pregnancy Benefit: As your breasts get bigger, your shoulders round forward. Strengthening the muscles between your shoulder blades helps counteract the slump.

Chest
Best Machine: Seated chest-press
Pregnancy Benefit: It's important to create muscle balance in your upper body by working your pecs.

Arms/Shoulders
Best Machines: Biceps and triceps
Pregnancy Benefit: Strong arms. Soon you'll be schlepping a baby, a diaper bag—and the groceries.

Lower body
Best Machines: Leg extension and seated leg-curl
Pregnancy Benefit: Your quadriceps and hamstrings bear the weight of your pregnancy as your belly grows.

Core
Best Exercise: Plank
Pregnancy Benefit: Keeping your abs strong will help prevent pregnancy-induced back pain.
How to: Lower onto all fours so your wrists are directly under your shoulders. Lift your knees off the floor (don't arch your back) so your body forms a straight line. Hold for 1 to 2 breaths, working up to 5 breaths.