The second trimester of pregnancy is definitely the best trimester. The morning sickness goes away and you finally start feeling better. You start to look pregnant and don't have to worry about people thinking you are just thickening up. You get to find out the gender of your baby. You aren't too big and uncomfortable yet. I love the second trimester.
I also love exercising during the second trimester. I don't have to worry about feeling like I am going to throw up all over my pilates mat. And I still feel like I can exercise without too many modifications.
Ironically the theme of the month is balance, and during your second trimester it is really important to focus on balance. I am not talking about finding balance in your day-to-day routines, I am talking about the try-not-to-fall-on-your-face type of balance! During the second trimester you really start putting on the pounds and your center of gravity changes. That is why it is really important to do exercises that help you find balance in your new body. Try to avoid exercises that have a higher risk of falling or abdominal injuries including: cycling, basketball, baseball, soccer, skating, horseback riding, etc.
And just like in life, sometimes we find balance when we start to slow down a little. While exercising, it is important to slow down in order to focus on balance. You need to slow down to avoid falling, especially after you can't see your feet anymore. And expect workouts to feel different. Even if you have been doing them for years before pregnancy, your body and sense of balance has changed. Plus, your ligaments are loosening and your hips are widening. You will have more hip and groin discomfort, so start to avoid excessive inner thigh and hip flexor stretches and strengthening exercises. And during your second trimester it is now time to stop lying flat on your back for more than 5 minutes (or sooner if you start feeling dizzy).
Remember your focus is on maintenance so don't push yourself too hard. And most importantly, listen to your body.
Here are a couple of videos with pilates exercises that are safe to do during your second trimester: