Running More Miles to Improve Race Times and Fitness

In order to become a faster runner, it's obvious that you need to-surprise!-run fast. Of course, this means doing a few days of "speedwork" in any given week, in the form of intervals, fartlek, or tempo runs, which I have written about in other articles.

Beyond that, though, there is another way to increase your strength and become a faster runner. It's obvious, but much easier said than done. Just start running more. Yes, even if the running is moderate or even slow, simply putting in the miles can do wonders for your race times.

How so? Well, for starters, running more will burn calories and help you lose any excess weight you might be hauling around. Even if you're pretty lean, as little as a few pounds of weight loss can make a big difference in terms of performance. Collegiate and elite athletes know this, and monitor their weight pretty closely.

However, there are other physiological reasons why running more aerobic miles helps your race time. First, it leads to greater mitochondrial density. The mitochondria are the "power plants" of cellular function. They actually are responsible for breaking down carbohydrate, protein and fat for energy. The more you run, the more mitochondria you will be packing. And the more mitochondria you have, the faster and farther you will be able to run.

Increased mitochondrial density isn't the only physiological change that occurs with increased mileage. Another is an increase in the number of capillaries in the body. Capillaries are the smallest blood vessels in the body, and are responsible for transporting many of the necessary ingredients for muscular contraction, including oxygen and water. Similar to mitochondria, the more capillaries your body has, the more efficient of a runner you will be.

Finally, running more increases the body's ability to store carbohydrates in the form of glycogen. Think of your body as a car and glycogen as gas. Unlike a car, however, you can essentially train your body to have a bigger gas tank by continuously depleting glycogen stores, then refueling. The best way to do this is with longer runs. However, for best results, make sure to refuel quickly (within 30 minutes) with a blend of carbohydrates and protein. Also, to maximize your ability to store more glycogen, the longer runs should be relatively fast.

With all the physiological advantages, it's little wonder that many elite runners log in excess of 100 miles per week. Obviously, though, not all of us are elite runners, so don't worry about taking things to that extreme. You can start by running daily or 6 days a week if you don't already do so. If you already do that, try increasing the length of one or two of your "easy" runs by a mile or two. Repeat the next week if your body seems to adapt easily enough-in other words, if this doesn't lead you to become excessively sore or tired. It's a good idea to cut back a bit on intervals or other speed workouts during a period of increased mileage. Also, after increasing your mileage for a few weeks in a row, cut back for a "rest" week to allow your body to adapt to the changes. You will probably feel like you need it at that point.

When increasing mileage, make sure to consume plenty of carbohydrates for energy and protein to rebuild muscle. You may actually gain weight initially when running more miles, but this is usually just water weight, as glycogen is stored with water as well. Hence, as the body becomes more efficient at storing glycogen, the scale may read a few pounds heavier. As long as you don't have to loosen the belt a notch, take heart that this gain is temporary and will recede.

In my college days, I ran the most I've ever run in my life, logging 100 mile weeks often and going as high as 120 miles. During that time I became very efficient and even though I never had much pure speed, managed to run a personal best marathon time of 2 hours and 44 minutes. I also became very lean, dropping to 8% body fat. This goes to show the kind of fitness gains that can happen if you have the time and commitment to run some more miles.