13. Track your heart rate: Wearing a heart rate monitor is like having a miniature personal trainer on your wrist: It will let you know when you need to work harder or ease up. Find your maximum heart rate (to do this, subtract your age from 220), and aim to work between 60 percent and 80 percent of that number.
14. Head for the hills: Roads with long, gradual inclines is a great way to keep your workout consistently intense. Rolling roads are ideal for intervals if you push your pace going up each hill and recover on the way down.
15. Value variety: As much as you might be digging your meditative walks or circuit workout routines, never do the same walking as exercise 2 days in a row, warns Smith. Instead, surprise your muscles (a surefire way to blast more calories) and keep things interesting (so you stay motivated) with this plan. Gauge your exertion on a scale from one to 10, with one being very easy and 10 being maximum effort.
Day 1: Long walk at a steady pace. Exertion: seven.
Day 2: Circuit workout (see tip No. 12). Exertion: six.
Day 3: Walk at a steady pace, up to a long, moderately steep hill. Exertion: seven or eight.
Day 4: Take the day off.
Day 5: Circuit workout as you did on Day 2, mixing in other resistance band moves. Exertion: six.
Day 6: Intervals walk (see tip No. 11). Exertion: six during rest-phase walking, nine during one-minute interval bursts.
Day 7: Easy, meditative walk. Exertion: five or six.