We all understand that in order to get into great shape, you have to exercise. Those who don't relish that thought almost alway ask how much do they have to exercise. I've written about this before and I've received comments that suggest that my everyday approach to fitness is wrong, unrealisitic, or unnecessary.
What kind of shape you get into and how fast you get there is directly related to your consistency. Ultimately, your habits will determine how far you get in improving your conditioning. You are the sum total of your habits. If you haven't established exercise as a habit, then you're not going to succeed in getting yourself into great shape. This is why I believe in exercising everyday: To establish exercise as a regular habit. If you allow being sedentary to become more habitual than exercise, then you'll set yourself back or fail outright.
Now, I'll be the first to admit that I don't beleive in killing yourself everyday. While most won't even come close to exercising beyond their physical limitations, its still possible to overtrain. Besides, it's a known fact that the body needs some rest. This doesn't have to mean skipping a day. It can be as simple as scaling back the difficulty or exercising different parts of the body. This is the key to the "train, not strain" mentality that boxers follow since the early days.
So, we have days where we work moderately hard and days where we work hard. If you're in good shape and aching for progress, then you should select one day where you push yourself a little bit BEYOND what you think you're capable of doing. A mandatory easy day follows afterwards. In addition to making yourself more physically powerful, it'll make you mentally stronger. Training like this demands that your mind forces your body to obey and do the work that it's presented. It's as much a mental exercise as it is a physical one at this point.
When you get right down to it, exercising your body should be as much a mental exercise as it is a physical one. It's about reformulating habits and establishing a strong mind-body relationship.