Just as you should be keeping a food journal, maintain a physical activity log. You can use an online tracking website (examples include: http://www.walkertracker.com/; http://www.crossfit.com/), a simple journal form, an app for your phone,etc. Consider buying quality tennis shoes for walking and a pedometer to track your daily steps.
How many steps should you be taking?
Recent guidelines suggest 10,000 steps a day which is close to 5 miles. You may need to work up to that. A reasonable goal is to increase by 500 steps a day. Check out The Walking Site at www.thewalkingsite.com/10000steps
