The average competitive runner runs 35.5 miles per week. Is that enough? Well, that depends. Let me answer the question this way: If 10 randomly-selected competitive runners were brought to me to discuss their goals and receive my advice, I would probably advise nine of them to run more.
Running more is the surest and most potent means to improve as a runner. The only other way is to run faster. Running faster is effective too, but its power is more limited. Running faster certainly yields improvement quickly, but it has less long-term potential to improve running performance than running more.
An analogy helps explain why. There are two ways to improve your standard of living. The first is to make each dollar you earn stretch further. For example: Finding a store where you can buy two apples for every dollar instead of just the one you get at the place where you currently shop. That’s one way.
The other way is to make more money. Now, which of these two options has more power to improve your standard of living? Without a doubt stretching dollars can yield improvements more quickly. You see results almost immediately. But you can only buy so many apples for a dollar. Increasing your income will take more time, but there’s almost no limit (theoretically) to how much money you could make, so the ultimate potential to improve your standard of living in this way is much greater.
Running faster is like stretching your dollars. If you’re currently running 35 miles per week and for whatever reason you wish to continue running 35 miles per week, you can improve quickly for a short time by running some of those miles faster. But you will improve more if you gradually increase your training volume to 60 miles per week. Of course, these two means of stimulating improvement are not mutually exclusive. You will improve the most if you gradually increase your mileage and then introduce a little faster running.
The best evidence from science and the real world suggest that the more we run, the better we race. A few good studies have shown that average and peak running mileage are the best predictors of performance in marathons. This pattern holds even at the highest levels of the sport. For example, Dr. Jason Karp found a strong correlation between training volume and performance in male and female qualifiers for the U.S. Olympic Team Trials marathons.
There is, of course, a point beyond which increased training becomes counterproductive. But that point seems to fall very close to the point of injury in most runners. In other words, runners keep improving as they increase their running mileage all the way until they get to one step short of the point of breakdown. Now, for some runners the point of breakdown occurs at a relatively low training volume. But while some runners can handle more mileage than others, the same principle applies to all: to get the best races results, you need to train almost as much as you physically can. It also bears noting that the amount of running any given runner can handle increases over time with a patient, incremental approach.
Anyone would expect a runner who increases his or her average running volume from 15 miles a week to 25 miles a week to improve. But why do runners continue to improve when they raise their average from 85 miles a week to 95, from 115 miles a week to 125? I think the main reason is neuromuscular. Every stride is stride practice, and the more you practice, the more relaxed and efficient your movements become. In this sense, doing a ton of running is beneficial for the same reason that playing a ton of golf is beneficial to golf performance.
The majority of everyday competitive runners don’t run anywhere near as much as they could. Thirty-five miles a week? Come on. Most runners don’t run more because they simply don’t feel like running more. That’s fine. I’m not here to tell you what you should feel like doing. But if you’re open to making a change, then I am here to encourage it. Instead of a race time goal, let your next goal as a runner be to build up to running a certain number of miles in a week. If you’ve never run more than 35 miles in a week, aim for 50. If your max is 50, go for 75. Take your time and slow down as much as necessary to keep your body feeling good.
When you’ve reached your goal, then reduce your mileage a bit and add some tempo runs and speed work to your schedule for a short time. Then race. You’ll go faster than ever.