Trust me, working with children under two for sixty hours per week will make the lbs. shrink away faster than you can say "Diet...??!" Just kidding. Well sort of.
It will be challenging to aim your focus on yourself when you are so busy, but just try to make healthy eating a priority. Hopefully the families you work for will have plenty of fresh fruit, veggies, etc. around for you and their child to consume during the day. Also, instead of juice...Drink plenty of water.
While engaging with your charges, include plenty of outdoor time. Toss a ball, play tag, etc. Just make sure you move vs. sit around. And while in the sun, don't forget to rub a little of your charge's sunscreen on yourself as well!
Most important, get as much rest as possible. While your charges nap, hopefully you can take a power nap or at the very least, lay down and relax for a few minutes or so.
Try to manage your stress levels too. If you have any issues or concerns with your bosses, try to address them early on so they do not stress your body out.
Good luck. Here's to a healthy Summer '05!