Found this at Sparkpeople.com and thought it was an intereting read:
1. Exercising early in the morning "jump starts" your metabolism, keeping it elevated for hours, sometimes for up to 24 hours! As a result, you’ll be burning more calories all day long—just because you exercised in the morning.
2. Exercising in the morning energizes you for the day—not to mention that gratifying feeling of virtue you have knowing you’ve done something disciplined and good for you. (Much better than a worm!)
3. Studies have shown that exercise significantly increases mental acuity—a benefit that lasts four to ten hours after your workout ends. Exercising in the a.m. means you get to harness that brainpower, instead of wasting it while you’re snoozing.
4. Assuming you make exercise a true priority, it shouldn’t be a major problem to get up 30 to 60 minutes earlier—especially since regular exercise generally means a higher quality of sleep, which in turn means you’ll probably require less sleep. (If getting up 30 to 60 minutes earlier each day seems too daunting, you can ease into it with 10 to 20 minutes at first.)
5. When you exercise at about the same time every morning—especially if you wake up regularly at about the same time—you’re regulating your body's endocrine system and circadian rhythms. Your body learns that you do the same thing just about every day, and it begins to prepare for waking and exercise several hours before you actually open your eyes. That’s beneficial because:
~Your body’s not “confused” by wildly changing wake-up times, which means waking up is much less painful. (You may even find that you don’t need an alarm clock most days.)
~Hormones prepare your body for exercise by regulating blood pressure, heart rate, blood flow to muscles, etc.
~Your metabolism, along with all the hormones involved in activity and exercise, begin to elevate while you're sleeping. As a result, you’ll feel more alert, energized, and ready to exercise when you do wake up.
6. Many people find that morning exercise has a tendency to regulate their appetite for the rest of the day. Not only do they eat less (since activity causes the release of endorphins, which in turn diminishes appetite), they also choose healthier portions of healthier foods.
7. People who consistently exercise find, sometimes to their great surprise, that the appointed time every morning evolves into something they look forward to. Besides the satisfaction of taking care of themselves, they find it’s a great time to plan their day, pray, or just think more clearly—things most of us often don’t get to do otherwise.
8. Exercising first thing in the morning is the most foolproof way to ensure that other things don’t overtake your fitness commitment, particularly if you have a hectic family life. (It’s so easy to wimp out in the evening, when we’re tired or faced with such tasks as rustling up dinner and helping with homework.)
9. More than 90% of those who exercise consistently have a morning fitness routine. If you want to exercise on a regular basis, the odds are in your favor if you squeeze your workout into the a.m.
10. Non-morning people can always trick themselves in the a.m. Having trouble psyching yourself up for a sunrise jog? Do what I did—tell yourself that you’ll still be so fast asleep that you won’t even remember—much less mind!