While trying to maintain a fitness regimen and be pregnant, I've obviously had to make allowances as this baby belly has grown. One thing I have made sure to do at each and every doctor's visit I have had from the get go is getting the green light on continuing my workout routine, or finding out what alterations I needed to make for each new phase. Trimester one, my workouts didn't really change from what my normal workout routine is aside from slowing down my running and cutting out my high intensity interval training. Trimester two, I cut out running completely around six and a half months and started lowering the amount of weight I was lifting. Typically, I prefer a heavier lifting routine where I do more weight, but less repetitions, but that is obviously not ideal while pregnant. This last trimester started out very similar to my second, but once I hit about eight months, baby boy has taken a growth spurt and I have had to change my workouts accordingly. My cardio pace has slowed considerably, so I added about ten minutes to each cardio session to account for the change in pace. I try to never let my heart rate get above 140 BPM (according to the HR monitor on the machines I use, which can be inaccurate, but I also go by how I'm feeling. I don't let myself get winded). I've given up using the rower, the step mill and even the treadmill hill climbs for the most part just due to the possibility of getting off balance.
For cardio, I stick to the elliptical and the Arc Trainer. I really can't wait until I can hop back on the rower and the step mill though, those are my favorites by far aside from running sprints. As for weight training, I've cut out any overhead weighted presses, I don't do any type of squats with the weight on my back. I tend to stick more towards the leg press these days instead just to have a bit more control over the movement. If I do any single leg exercises, like single leg deadlifts, single leg squats, etc, I use a bench or chair for balance just because my balance point is ever shifting as my belly grows. Lastly, the amount of weight I'm currently lifting is about half of what I was lifting around the first trimester. For example, I was doing five unassisted pullups in a set, now I use the assisted pullup machine and only lift about half of my body weight on the machine. I was deadlifting about 75 pounds, now I'm doing around 35 with dumbbells instead of the barbell and plates.
As for the occasional barre workouts I do, I use my dvd's at home and haven't had to make any changes to what I do aside from not doing the ab portion of the workouts any more. I do still try to get in plenty of planks, both traditional and side planks and lots of low back work to keep my core as strong as possible. Please keep in mind that this is just what has worked for me during my pregnancy. The way I've worked out this time is very different that how I worked out while pregnant with Caroline and I feel like thus far, this has really helped me continue to rest well at night, have energy most of the time during the days and I sincerely hope that it will help me to have a quick recovery after birth so that Caroline doesn't have to have her days altered much for too long. The two most important things about working out while pregnant, in my opinion, are to listen to your body and listen to your doctor. Even if all you do is take a walk most days of the week, you're still doing yourself a big mental and physical favor.