It's ok to start an exercise routine during pregnancy, even if you haven't been doing it regularly, but as we always recommend, first check with your doctor.
One of the things to consider is that pregnancy is not the time to try to lose weight or to start exercising vigorously, but if so far everything has gone well, and you do not have a high-risk pregnancy, you can begin a mild or moderate activity regime.
The intention is not to participate in a triathlon or to run a marathon, doing some physical activity during the pregnancy is beneficial for the most women. Despite the fact that there is no objective evidence that athletes have a "shorter or less complicated" delivery, there is evidence that women who exercise regularly can recover the weight, strength and flexibility that they had before pregnancy more quickly than sedentary women.
As we said before, it is recommended during this period you talk with your doctor before starting any exercise program. The most suggested exercises are walking, swimming, stationary, yoga, pilates and tai chi. In general, it is recommended to be in intensity ranges between 60-70% of the maximum heart rate. You should do it on a regular basis, around 30 to 40 minutes a day, between 3 to 5 times a week.
For a more advanced training, you can start running if you have an uncomplicated pregnancy and your doctor approves it, even if you have never tried to run before. Just remember to start slowly. Warm up for 5 to 10 minutes, then run slowly at a comfortable pace for 5 minutes and cool by walking for another 10 minutes.
If your joints do not bother you and you feel you can do more, little by little you could increase the pace and start running longer distances. Later in your pregnancy, you will need to modify your routine or slow down, as your tummy grows.
Lifting weights and other exercises that involve standing for long periods of time can be do it, but do it with an expert like a personal trainer to avoid complications.
If you want to ride a bicycle, you should do it with caution. If you are an expert cyclist, you could continue to do it without a problem in the first trimester. Some experts believe that it is dangerous to ride a bicycle in the second and third trimesters of pregnancy since the centre of gravity changes and affects your balance, which makes the risk of falls increase.
A fixed bicycle is a safer option when the pregnancy is advanced.
Being pregnant doesn't mean that you should stop exercising. Physical activity can help you to recover your body and weight easier than by not exercising. You shouldn't feel limited by the type of exercise that you can do but always check with your doctor first to ensure that the activity is appropriate for you and see a health professional to secure the use of right technic.