Good for you for quitting smoking! It's great for you, for your family, and for your budget! Exercise is great to help you fill those times when you really want a smoke.
My husband is a discilplined jogger, and he goes for distance rather than speed/time. My son is a varsity cross country and track runner with numerous high school records. I'm a treadmill walker. So we know a lot about running in our house!
Definitely get very good shoes - go to a running store like PR Running in Westboro. A good store will watch you walk or run (they'll either put you on a treadmill or watch you run up and down the sidewalk) to look at your stride, degree of pronation, etc. Then they will put you in a good shoe designed for your foot and the type of running you do. I am not sure that the mall sports stores have people who really know what they're doing. I know that most serious runners, including kids on the high school teams, tend to buy from real running experts.
I'm no champ, but I went for a $90 pair of shoes (which is the low end!) so I would get the right support and not have any pain or injuries that would cause me to quit. Then I wear really cheap clothes to make up for it! It sounds expensive, but just look at your former cigarette bill, and figure that you spent $90 for a certain period of time, but your shoes will last a lot longer than that! Also, good running stores will check your shoes for you as you go along and let you know if there is still support in them, or whether you need to get new ones. It's not based on time, more on mileage. My son actually changes shoes after a certain number of miles, just like oil changes in the car.
Then I would get an underneath layer of wicking material for your first shirt and leggings. YOu don't want the sweat to stay against your skin - you'll get wet and cold. Under Armor makes some, but so do other manufacturers. You can try Target as well as running stores and even camping stores. REI often has garage sales and you can get great deals - if stuff has a stain or a few hanging threads, who cares? No one will see you! Then wear a few layers on top of that, with a hat and gloves and something wind-proof. Be sure you can move easily. Be sure you have something reflective. If you are going to be running in the dark, get a headlight - my husband got one at WalMart for about $15 in the camping section. It helps him spot potholes, leaves and ice patches, and that is really important.
Don't worry too much about how much you are doing - just make it a pace you can stick with, and it's fine to mix up jogging and walking. You might wear a pedometer - they are cheap. Wear it all day and count your steps doing other things, like chasing the kids around. You'll be surprised at how much you move. If you add a little each weak, you'll see your body tone up and you will feel great and energized.
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