The standard three-days-a-week is fine for staying healthy, but not losing weight. For most people, I advocate five to six days a week. Three-days-per-week is a good starting point for beginners, but as you progress and your fitness improves, add those extra days. Not only does working out more days increase your benefits, it teaches you to make fitness a regular part of your daily ritual, which helps you maintain consistency.

Any activity you do contributes to burning calories. Five minutes is always better than nothing. But when you exercise for at least 30 minutes, your cardio reaches a level where everything happens more quickly. You burn more calories, trigger more enzyme changes and raise your core temperature, which can dull your appetite.

While 30 minutes may feel like an eternity, it's easy to hit. Begin with 15 minutes of exercise and then add two to three minutes to each routine. Within a week or so you'll be up to 30 minutes.

When you perform aerobic exercise at a moderately high intensity you increase your metabolism, which is what triggers effective fat loss. How do you do that? Aim to work out at your optimal cardio intensity—also known as "the zone." My favorite approach for finding the zone is perceived exertion. I've found it works well with the majority of my clients, no matter their current fitness level.

Here, you simply rate your overall intensity level on a scale of zero to 10—zero being how you feel at rest, and 10 an exertion level so intense you can only maintain it for a moment. Perceived exertion is based primarily on your breathing, which becomes elevated as your oxygen needs increase. This provides a quick gauge of your intensity level. Work harder, you need more oxygen, thus, you breathe more rapidly.

Too Tired to Exercise? Make a Date
When obstacles threaten to keep you from working out, use the following quick and easy motivational tips to stay on track.

Set up a standing date with a friend whose fitness level matches yours. Your mutual motivation lulls will cancel each other out. Research shows that having a dedicated workout partner makes you more likely to stick with an exercise program. Your mutual motivation lulls will cancel each other out. Research shows that having a dedicated workout partner makes you more likely to stick with an exercise program.

Tie up Your Shoes
Think baby steps. If you truly don't feel like you can get out the door, just put on your workout clothes. If that feels good, throw on some sneakers. Even if you stay in the house, the clothes give you an increased range of motion, so you'll probably put more energy into your chores.

Pile on the Rewards
Women tend to save rewards for distant, huge goals like a 20-pound weight loss or three lost dress sizes. Rather than making goals destination-oriented, make them behavior-oriented. Set a goal to work out three times this week, and when you achieve it, give yourself a nonfood reward like a glossy magazine or new nail polish—little indulgences you wouldn't ordinarily give yourself.

Pump up the Volume
Listening to music eases exercise in three ways: It distracts you from fatigue, it encourages coordination and it relaxes your muscles to encourage blood flow. If music doesn't work, try a book on tape.

Return to the '50s
Open the garage door manually, switch the channels on the TV without the remote, wash your car and dishes by hand, and hang your laundry outside instead of throwing it into the dryer. It's estimated that in the past 25 years, labor-saving devices have decreased the number of calories we burn by 800 a day. That's about a pound and a half per week!

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When Canadian researchers followed more than 2,000 employees for four months, they found that those who received weekly e-mails containing fitness and nutrition tips exercised 13 percent more and ate better than those who didn't receive in-box reminders.