If you struggle with convincing your children to play outside... Place a basket, tote, box by the door with outside toys in it. And every week switch the contents with a new selection. There is no need to spend money on new items. Re-purpose items. Check out freecycle. Lots of websites with lists of activities and games. Spend a wee bit of time researching and reminiscing. Take the opportunity to teach the kids a new game.
As a mom, my biggest stumbling block can be having time to make sure I'm eating nutritiously. I start the week out with a plan of how I'm going to eat for the whole week, a framework. I will make myself one or two healthy meals on the weekend that freeze well to grab during the week. I try to eat mostly the same during a given week, the predictability of knowing what I need to take to work for lunch and snacks is less stressful than trying to think of new things each day.
Think your child is too small to exercise with you? I walk or run after my 4 y/o as he rides his bike ahead of me. I have him stop at every intersection so I can catch up. It keeps my pace up, helps me to keep an eye on him, and encourages family exercise. He is always shouting, "Run Mom!" when I slow down, so it's like having a free personal trainer!
I wasn't able to get my full workouts in because my daughter is special needs so I learned to work her into my workouts. Whether it is a Jillian DVD or hiking, I give her something to do to help me and then I am able to get a workout in - even if not as high an intensity, it is still activity!
Rather than take away a privilege, my children earn their privileges. Everyday they are expected to cooperate. They can earn up to 9 sticks in a day (3 sticks 3x a day) If they earn 6/9 sticks they earn privileges for the next day. If not, the following day is very boring but they can try again!