Pushing the Pace: Achieving a New Personal Best
In many ways, the human body is much like an engine. It achieves a certain level of efficiency at a given speed, and that efficiency slants downward on either side of that ideal speed (when speed is increased or decreased). Efficiency with an automobile, however, is very different than physiological efficiency. A car simply burns fuel at a certain rate, and changes in fuel consumption represent changes in efficiency. With the body, fuel consumption only becomes important in extreme events like Ironman Triathlons and ultramarathons (the standard 26.2 mile marathon is usually too short for food to be a problem).
Efficiency, then, is measured in how much energy you put into the motion of running ( measured in joules), and how much energy it takes for your body to travel at a given speed. Everyone's form has little inefficiencies: when I run, for example, I tend to lean forward as I get increasingly tired, and my poor posture means a lower return for the energy I put into the motion of running. Improving this aspect of efficiency takes years of coaching and continued maintenance.
What can be expressed easily in words is the second aspect of efficiency: the psychological attitude during running. If you want to improve your speed and run in a more even pace, I know of no other way to express how to do this other than the fact that you must be hungry for it. You have to be willing to fight the factors that are holding you back from a personal best and slowing you down. There is a definite barrier of pain and effort that has to be broken through in order to continue the progression through faster times. If you don't want to feel the burn of lactic acid that can come during a high amount of physical effort, your body will know what your mind is thinking and prevent you from running that fast.
What is pain during running, then? Is it anything to be afraid of? Certainly not. In fact, your body has you quite well covered. To reward your physical effort, the body injects generous doses of adrenaline during heavy exercise, so you rarely feel intense pain unless something is wrong. A burning or aching feeling is entirely normal; this just means your muscles are working. And, after you complete heavy exercise, your body initiates a flow of endorphins to cover any post-race muscular pain that would occur. Have you heard the term "runner's high"? Endorphins are naturally-occurring opiates that can totally block the reception of pain! This leaves you feeling awesome after a workout, and is a great reward for a job well done.
The way to find that personal best you have been seeking is to link the psychological attitude of desire with the tangible result you want. In cross country, we achieved this mainly through the use of speed workouts. Our coaches would sit down with us at the beginning of the season and ask us what our goals were; they would then tailor the speed of our workouts according to how fast we wanted to run. Speed workouts, believe it or not, are fantastic at increasing both speed and endurance. I am a fan of 400-meter workouts (that is, 1/4 mile or 440 yards). We used to run 8 to 12 of these sprints at one time, and by the last 4 to 6, it was no longer a speed test but a test of endurance to see if you could make it to the end of the lap. But, by examining the split times of our sprints, we could see what we needed to work on in order to improve our personal bests.
Track is a much easier sport to analyze by splits, because the laps never change and are completely constant. It is here that you can watch runners and see where their mental and physical efficiency degrades: somewhere in the range of 50%-80% completion of the race. In the 1600 meter (four laps or about one mile) race, you can pretty much bet that everyone's weakest lap is going to be the third lap. In the 3200 meter race, runners usually slow down on the 5th and 6th laps.
There is simple logic for why people slow down at about this point during a race: the body is beginning to get tired, and it's quite difficult to maintain a constant pace with an increasing level of effort. There's also a completely logical reason why runners rarely need to be encouraged to run faster in the early or later parts of races: the excitement of the start and finish causes a natural increase in pace.
What you need to focus on, then, is to encourage your body to maintain an even pace. If you are trying to break your 5k personal best, seek to push hard during the middle or second mile, and you will find that the other miles fall into place. During your long training runs, try pushing the pace for a few miles during the middle part of the run. This type of habit will reinforce the effect you are trying to produce. Above all, improvement is simply a factor of the miles and effort that you put into your training. If you are patient and try enough new techniques (and if you want that personal best bad enough), then you will eventually find what you are looking for.