I am a mum of four small children so finding the time to exercise is always hard, especially as you only have small pockets of time during the day/evening that a) you feel like you could exercise b) when you can exercise and c) before you go to bed at a ridiculously earlier time because you don't have the strength to keep your eyes open.
I did quite a lot of exercise before I had my first child so I had a good idea of what felt right for me whilst pregnant (if you are new to exercise or have any concerns please visit your GP). I managed to run whilst pregnant and as I grew this became a walk run to eventually fast walking which although I was tired it helped so much especially with the birth. I also did gentle gym workouts and the odd class to help me to feel good whilst my body was going through such a huge change. After the baby it was hard to get straight back into exercise for all of the obviously reasons, but more importantly I made sure not to stress myself when I could no longer reach the goals I did before having my baby. After four children I now know that eventually you can get back into the same shape you once were it just takes time and a great deal more effort, but the rewards far outweigh not doing it, hence finding the time to exercise after baby number four.
I admit I no longer have the same goals, they do change, but in a good way. Its so hard to motivate yourself in the evenings when your children finally go to sleep, but I find that when I make the effort and go to a class or go for a run the first 5 mins are so tiring but once I get going I feel great and realise that exercising gives me energy, clears my head, switches me from mummy mode to doing something for me, this is something we can easily forget about.
Even if you simply fit in a walk or do a class once a week it has so many benefits for you as a parent, sometimes you don't know it at the time but it really does help on so many levels.
I'm so happy I continued to exercise during all of my pregnancies as it helped me to regain my figure, this I found with each baby was a little harder as finding the time was tricky but by slowly having little goals I eventually got there, a year after the baby arrived I felt like me and looked like me again.
Exercising has helped me so much with being a parent, there are so many different reasons but each one will be different for everyone, my advice is to take it easy, don't set unrealistic goals for yourself because there is already pressure on you as a parent, you will get to where you want to be, it will take time after having children but that's ok. Set small goals and choose something you like doing that way you will sustain it and importantly have fun!