Here's a great Q & A from a pilates instructor regarding the energy boost a good workout gives. It's very well put and the author ties in some great scientific information in a way that makes it easy to understand.
Q. My friends say that working out will increase my energy level. But, when I'm already feeling tired, how is exercising going to give me more energy?
A. In a world full of energy bars and overloaded caffeine drinks, many people often overlook the best option for getting that highly sought after energy boost -- exercise.
Exercise is a very powerful "life tool" that has been shown to increase endorphin levels. These endorphins are the hormones often linked to the "high" or "rush" you get from a challenging physical exertion. It definitely lifts your spirits and makes you feel more alive. While it might seem contradictory to say that you should work out when you're already fatigued, scientific studies have shown that regular exercise does increase energy and reduce tiredness.
There are many immediate benefits to a workout that are not only physical, but mental and emotional as well. What better way to feel alive than to get a real reminder of what it means to be alive? Exercise gets you up and moving, your heart pumping, and brings the focus back to the basics of life -- mainly your breathing. It can also help you feel strong and powerful, which is the best way to boost your self-esteem and add a little lift in your step.
In the long run, exercise can go from being an instant energy boost to increasing your overall energy. A fit body produces stronger muscles -- muscles that will improve your endurance throughout the entire day. A fit heart makes it easier to breathe and stay active for longer periods of time -- without feeling weak and short of breath. Besides the benefits you see during the day, exercise has also been shown to improve your overall quality of sleep (which, of course, will reduce how tired you're feeling).
So, when you're feeling like your energy tank is low, get your body moving. You'll get a much-needed recharge and feel like you've accomplished something great for your mind, body and soul.