It’s Fine If You Break the 10% Rule
There is a lot of discussion in the running world about how to safely increase your mileage from week to week. The general piece of advice given is to increase your total mileage no more than 10% from one week to the next. As a general rule of thumb, this works. But it’s not applicable at every point in your training.
If you’re just getting into running, don’t worry about the 10% rule. Spend the first two or three weeks just getting used to running. Take it slow. I say this because you can still get injured from overtraining even if you properly warm up, stretch, and cool down for every workout. Go on two or three mile runs maybe three times a week. Your body will need time to adapt to running. As the weeks go by, you can add more runs in your weekly schedule. Don’t concern yourself with reaching a certain time or even reaching a certain amount of mileage.
Runners with more experience may find it easier to progress more quickly than by 10% every week. This can be true even when an experienced runner is starting training again after a week or two weeks off. An experienced runner who was running 35 miles a week before a week-long break may find it feasible to run 20 miles a week upon returning.
I’ve noticed in myself, at the age of twenty-six, how much easier it is to build mileage than it was when I was eighteen. Last year, it took me four weeks to build up from running 17 miles a week to getting a personal record in a half marathon. The week before I ran 17 miles, I ran 12 miles and wasn’t really focused on training for a half marathon because of work. When I was eighteen, it took me about two months to build up my mileage so I could run my first half marathon. Needless to say, the more you run, the easier it will be for you to get a good sense of how to increase your mileage. That might mean increasing mileage by 20% one week or not at all another week.
Lastly, let me say that consistency will help you increase your endurance the most. When you think of weekly mileage, remember that this is mileage over a seven-day period. This is a bit short-sighted. Think about how many miles you run in a month and even beyond that, how many miles you run in three months or a year. It’s important to have a wider scope since injuries as a result of overtraining can build up over the course of weeks. After I ran a PR in a half marathon last year, I found myself injured three weeks later. I was running fartleks and as I took my last step in a 300 meter sprint, I felt a sharp pain in my right heel. I was eager to break my PR again and hadn’t considered the cumulative effect of two physically intense workouts a week for a few weeks. In retrospect, the injury made sense. I had spent considerably more time running in a span of eight weeks than I had spent when I ran somewhat consistently the two months before that.
Running consistently for not just weeks but months will make it easier for you to increase your mileage injury-free. This seems to be saying this obvious, but the emotional high of a PR can make you feel, like I did, that your body is indestructible. It’s not.
It’s fine if you break the 10% rule, but pay attention to your body and consider how many miles you’ve run (and at what intensity) over a month or two in comparison to what you ran before over the course of a year.
